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PostPosted: Tue Dec 07, 2021 1:14 am 
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Phil,

The USS MANCHESTER images online at NARA come from what is called the 19-NN collection. Basically these are scans of the NEGATIVES of what would otherwise have been 19-LCM prints from the 1950's. What happened with the prints originally made from these negatives, was that before they got turned over to NARA by the USN, the photos were ruined by flood waters in their storage location. But the negatives were cold storage elsewhere and were safe. NARA started to scan these negatives a few years back, and since they were digitized, they were good candidates to put online. NARA College Park has these digital images on dedicated hard-drives in the Photo Collections Research Room (5th floor) at College Park, MD. Researchers can sign-out the hard-drives and are allowed to download these images to their own computer or storage device. I downloaded the USS MANCHESTER images after her 3-in/50 RFG upgrade, since she was always an interesting subject to me. Plus I downloaded the USS JUNEAU II (CLAA-119) after she also had her 3-in/50 RFG upgrade. Both units were the only units of their classes to have been upgraded with 3-in guns.

The only problem I have with these images, is that NARA's idea of "high-res" is scanning at 300 dpi. I and most of the guys I go to NARA with, scan photos/negs at a min of 600 dpi. We think of 300 dpi as "Medium-Res". 300 dpi is fine if the subject fills the whole frame, but when the subject is a distant view, it won't allow the subject image to be blown-up without risk of pixelating. The resolution of 3150x2557 pixels per image shows that the original negs are ~8x10.

NHC/NHHC has some of these original prints in their "NH" collection at the Washington Navy Yard. A few years back now, NHHC contracted to have "most" of their collection of photos digitized (not by scanning, but by digital cameras), aka photos with "NH" numbers. There are other photos in their "L-file" of misc "Leftover" photos not cataloged as "NH" photos, that were not digitized.


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PostPosted: Wed Dec 08, 2021 12:53 am 
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Rick,

Thanks. I agree that 300 dpi is the minimum useful scanning density. I also normally scan prints at 600 dpi. But for some old prints made with very fine grain emulsions (before "fast" films were developed) I sometimes scan at 1200 dpi.

Of course "high resolution" is a matter of opinion. For me a "good" resolution is when the full frame maximum width is 3000-4000 pixels. This allows me to "zoom" in and see some detail. 6000 pixels or greater in even better. But there will always be a limit to how far you can enlarge a part of an image. Zooming in on part of a wide angle image to see details of a small object is a poor substitute for a full frame original photo of the object of interest. But, of course, such images often don't exist.

The fundamental limit is the graininess of the original. Once you get to the point you can distinguish individual grains in the photo emulsion there is nothing to be gained by higher scan pixel density.

I used to take a lot of pictures with High Speed Ektachrome (ASA/ISO 400) 35mm slide film. I have a film scanner that will make 4000 dpi scans, and I can make out individual grains in the Ektachrome film! So there would be no point in scanning at a higher resolution. However, I also shot Kodachrome (ASA/ISO 32 and 64) and the grains are not visible at 4000 dpi.

When I started working with NARA microfilm (copies) I experimented with scan densities. The scanner I was using (at our local library) would do up to "800 dpi" (when scanning paper sheets or photos) but no one knew what that actually meant with film scanning. At "600 dpi" the images produced from microfilm were 6600x5104 pixels - 33.7 megapixels.

However, scanning a full 35mm frame at this resolution produced images that were too blurry to read the smallest print on the original 36" high paper blueprint sheets. The smallest letters were only 4-6 pixels high.

Then I scanned each 35mm frame in six (3x2) slightly overlapping images. After merging the images in Photoshop the resulting 142 megapixel image (14595x9730 dpi) was the equivalent of scanning the film at about 10900 dpi. At that resolution the grain was not visible in the archival film used to photograph the blueprints! It was about equivalent to scanning the original paper blueprints at 300 dpi. Normal print letters are about 30 pixels high and that makes the text readable. I can even distinguish the hand writing of the individual draftsmen.

To my amazement in some of the images I can see the extremely tiny pencil dots the original draftsman used to mark the centers of circles and to set the line spacing for the hand written text! However, most of the originals are not quite this clear.

Phil

PS: More pixels are not always better. I have a cell phone that takes 64 megapixel images. The image quality produced by the tiny cell phone lens is pretty bad. It is not nearly as good as the 24 megapixel images from my DSLR camera with high quality lenses!

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PostPosted: Wed Dec 08, 2021 1:41 pm 
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Phil,

I agree on what you say.

At NARA the prints I scan are primarily from the BuShips (19-LCM and derivatives) collections and 80-G Misc USN Images. For the BuShips photos, NARA has the negatives, at least for most of them. Until about five years ago the only way to get scanned copies of Color Transparencies (80-GK for USN color images) of originals (not the 35-mm copy slides) and for B&W negatives (when an original print wasn't available), was to order one from a small group of authorized vendors. Since then, NARA policy changed and researchers could, if allowed to, make scans of the transparencies and negatives. BUT, you had to either have an APPROVED scanner (very expensive) or need to use the scanners NARA provides. This for me opened up opportunities to get high-res copies of many photos that I either knew existed because they had appeared in older publications or of photos I was unaware of. Many original photos "simply" walked out of NARA's building downtown prior to College Park being built and the photo collections transferred to it. So getting access to negatives was a big boost to research/collecting images. Most transparencies are 5x7 and most of the B&W negatives of yard photos are either 8x10 or 5x7. Great high-res images.

For 80-G images, at least for WWII and prior era, there aren't ORIGINAL negatives for most of the photo prints mounted on cards. The USN made COPY negatives of these prints for reproduction purposes. So, it isn't normally worth pulling 80-G negatives. But, many 80-G prints found on mounting cards were taken with large format cameras and are actually quite nice and can be scanned at high res. I have been able to take some really small prints and scan at a very high dpi and get a very nice image. One image of an "unknown" destroyer from the Fall of 1941 alongside USS ENTERPRISE I came across was only about 1.5-in square. I scanned it at a really high dpi not expecting much, but when I did, I could read the ship's name on a life ring!

I have come to the conclusion after talking to old hands, that many of the 80-G type photos taken during battle action, are actually single frames from a movie film taken by typical 16-mm or larger movie cameras in use. As you say it isn't worth trying to scan these at a very high-res.

Some of my best "finds" are photos in Textual Records folders, that are not found in 19-LCM or 80-G.


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PostPosted: Sun Dec 26, 2021 5:33 pm 
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Being able to do useful pixel peeping depends on how close to the original image one is. Every scan, print, reprint or whatever looses information. 300 DPI is a typical printer resolution, but not a good resolution for scanning an image intended for enlargement. The small but really high resolution images that Phil was referring to were undoubtedly contact prints. Back in the 30's and 40's when landscape photographers were running around with 8x10 view cameras they often made very high quality contact prints directly from the negatives, super simple equipment required. Such images can be explored with a loupe and have a surreal dreamy quality about them. Before the digital revolution I ran around with a 4x5 Linhoff monorail camera and carried my 6x6 cm Hasselblad all over the Arctic Wilderness. With the coming of high quality digital I found that my Hasselblad 50 MP digichromes were at least as good as the 4x5 film and that my 50 MP Canon was as good as my 6x6 cm film images. More MP can be important with high quality optics. Aerial images taken of Denali with climbers in the image the difference between 25 and 50 MP was that the larger image, the climbers had TWO legs. These of course using high quality Zeiss and Canon L optics. In aerial I found an advantage of shooting at a high frame rate and tasing several images. The first in a series would suffer from minor image shake from shutter activation, the second shot in the series would not encounter this. The Hassel-bad being a single shot with digits moved forward by a hand crank benefited form the use of a pistol grip.

The yard photos, possibly taken with 4x5 press cameras, seem to be the clearest images. Negatives, if stored under good conditions will probably outlast digital files. Model makers can and should be historians. Flight sim also has virtual modeling with an added historical feature in that you could 'fly" them. I did flight dynamics for many aircraft, quite a number of one's I had actually flow, the others based on some 25,000 hours of all sorts of aircraft, I could usually make good sense of the performance data and pilot notes. I would unfortunately get irritated with comments from guys who hadn't flown anything criticizing my iteration od an airplane I have maybe made a thousand takeoff and landings in real life. Even more rivet counters in that world.

Many thanks to those of you who have aided with the research and necessary supposition about form and function. We do the best we can with the available information!

Thank you.... Tom


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PostPosted: Mon Dec 27, 2021 1:44 pm 
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Actually, many of the in-yard photos, particularly MINY, are 8x10 negatives. I found out after researchers at NARA were allowed to pull and scan negatives (of photos where the prints are missing from 19-LCM {BuShips Photo Collection}) and sometimes got 4x5 negatives and many times got 8x10 negatives. Scanning of the original B&W negatives produces a "lighter" image than prints made from them. The "darker" and many times more balanced images on prints come from darkroom processing selection of paper used, settings in exposure time under the enlarger/light, and chemical processing skill.

How long "digital images" will last is still an unknown. Depending on storage media and usage of those images will vary survivability. I know that standard DVD/CD formats do degrade. HHD drives are mechanical devices and had "crash" as many of us known. :Mad_5: SSD Flash-Drive devices are still somewhat of an unknown. I have on occasion had Flash-Drives just die, never to return. But, how long they will remain useable if stored in stable environments is to me an unknown factor. I definitely don't trust or recommend storage in the "cloud".


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PostPosted: Mon Dec 27, 2021 11:24 pm 
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It has been several years since I read the data sheets of flash memory, but every technology I know of depends upon charge storage within the silicon layer structure. Because everything has a finite resistance, it is only a matter of time before the charge bleeds off and the data is lost.

Know-it-alls on the Internet say flash memory will hold 10 years. But I think that is a guess. Memory cells in flash memory "wear out." Writing causes atoms to migrate, and the original distribution changes with each write. So flash devices that are used a lot will see faster degradation of the memory cells. 30 years ago flash memories were guaranteed to last through 10,000 write cycles. Today they say 100,000. I still have my first 256K USB flash memory stick from 1990, and it still works OK. And I use it quite often.

Because overuse "wears out" memory locations, flash memory devices have on-board processors that use an algorithm to readdress writes and reads. It is the nature of software to start writing at address 0 and proceed until all the data is written. Therefore, address 0 gets hammered a lot more than address 1,000,000. But the on-board algorithm readdresses 0 and subsequent frequently used addresses to different places within the memory array so that every memory cell in the device gets about equal usage. Just thinking about the complications in how this works hurts my brain!

Phil

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PostPosted: Tue Dec 28, 2021 12:04 pm 
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I still have a couple of 256K SD cards. With the size of current images They can be used like sheet film for a single image, one just doesn't have to fuss with a dark slide. There are some advertisements for digitizers that will take your analogue media (film etc) and make it last "forever", a term which has lost popular meaning when some poli (more?) ticians scream the planet ends in whatever number of years they promote. I'm old enough remember when Seattle had 5000' of ice on top of it.... Then there is the stuff I stored on 3 1/2" disks?

My BMW has a tape player and I still have the sound track to Victory at Sea, one of Rogers and Hammerstein's better efforts. In hopes that the archives will retain the analogue originals and not digitize and discard.

The Clevelands? Great ships!


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PostPosted: Tue Dec 28, 2021 12:12 pm 
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I'm still able to pull files off CD ROMs I burned in the late 1990s. To me the ideal situation for storage would be 1) backups on CD ROMs, 2) digitized copies stored locally on platter hard drives (not solid state drives which apparently are less reliable than platter drives, though I've never seen one fail...yet), and 3) stored with a cloud provider like Dropbox for access when you are not in your home office.

Cloud providers of course come with their own issues (having to pay $20/month for 2TB of storage on Dropbox isn't great) and shouldn't be relied on as the "only" storage method -- but they do provide redundancy if (say) your house were to burn down taking your archive disks and computer with it...

I will echo Fliger747's comments about hoping NARA continues to store the analog originals. Digital records are great for easy access and searchability but they don't seem as robust as having physical copies somewhere...


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PostPosted: Tue Dec 28, 2021 4:37 pm 
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Ian,

OR you can do like I do after I experienced a hard drive crash on my first laptop I was using to scan at NARA my first year there (I had backed up my images on DVD/CD's before the crash), I make MULTIPLE Back-up copies on several computers and storage devices and distribute say 4 or 5 HD or SSD to friends in different parts of the country, in case the Ice Age gets to your house and some of their houses, but hopefully not all. :big_grin: :big_grin:

Plus I have always had a dislike of going through all the digital scanned document pages I have. I mean 1,000's and 1,000's of pages. So I got a B&W laser printer and print out the pages and put them in binders. It is easier for me to flip through pages and have multiple "folders" open to jump to and forth. Of course I how have 6-ft plus of binders on a shelf. :shock:

An aside; NARA is pushing to scan and put everything online. Even to the point they have started to not allow pulling something that had been scanned and uploaded online. Well, if you are at NARA and want answer to say date a photo in War Diaries and/or Deck Logs, using their HORRIBLE WiFi to search their POORLY DESIGNED website is a painful experience of slow as dial-up service. Strangely, if you access from Home, the website is faster.


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PostPosted: Tue Dec 28, 2021 10:56 pm 
"Victory At Sea" was strictly Rodger's work.


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PostPosted: Wed Dec 29, 2021 12:48 am 
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Tom,

I still have a few 8" floppy disks, but I backed up almost all of them to 5 1/4" in the 1980s and I have a drawer of them. I do have one computer with dual double sided 8" floppy drives - it was the first computer I designed completely from scratch, and I keep it for the memories. It had dual CPU processors, a 64 bit floating point math co-processor and a memory management unit like mainframes use to quadruple the memory space of the CPU. That isn't saying much - it was an 8 bit Z80 CPU (12 MHz!!) with a 64 Kilobyte address space, which I expanded to a whopping 256 kilobytes back in 1982. 256 Kilobytes of dynamic ram cost $1000 back in those days!!!

****

I had a brother-in-law, three sisters-in-law and assorted more distant relatives working at JPL in Pasadena in the 1990s. I visited their library, which had rows and rows of bookshelves with ring binders full of the original photos from every spacecraft the US had launched. The original data was stored on magnetic tapes, and in one corner was a pile of DVDs stacked from floor to ceiling (literally). They had a person transferring the data from mag tapes to DVDs, but the tapes were failing faster than they could be copied! The person didn't have time to organize the DVDS so they just got tossed onto the pile until someone had time to put them on shelves. A lot of the original data was lost with the failing mag tapes. Now I wonder what they are doing to back up the old DVDs.

Phil

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PostPosted: Mon Jan 03, 2022 12:46 pm 
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My ex sister in law is a computer geek for Boeing. Her job was making all that test and design data done from the punch card era still useable. "Progress is our most important product", remember that line?

Model ship builders become historians!

Tom


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PostPosted: Wed Jan 05, 2022 11:37 am 
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This is a shot in the dark, but speaking of the Manchester CL-83 has anybody here ever run across any photos of her under construction, from her keel laying up to her launching?


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PostPosted: Wed Jan 05, 2022 2:59 pm 
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"Vic"?,

You are asking for "Progress Views". Builders submitted "In Progress Photos" during construction for submittal to BuShips, how often varied with different builders. I went through the BuShips (19-LCM) folder for USS MANCHESTER at NARA and didn't scan Progress Views for her, other than showing her fitting-out. I'm not sure if there were any in the folder. There could be such views in MANCHESTER's BuShips textual records. I have run into those for the destroyers I research. I normally don't scan the early construction views, keel laying, build-up of the hull, etc, unless something interesting is shown. Normally the construction photos I'm interested in are towards the end of construction. I did scan images of her sister, USS PROVIDENCE (CL-82), just prior to her launching. They were great shots of the hull shape and underwater hull details. But, nothing of the keel laying or internal hull.


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PostPosted: Wed Jan 05, 2022 4:17 pm 
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Thanks for the feedback Rick. The reason I asked if anybody had any "Progress Views" of the Manchester is because I've been trying to deduce which ships occupied which slipways at the Fore River Shipyard during the WWII era. Admittedly a rather esoteric if not pointless endeavor. At any rate Navsource has a number "Progress Photos" of various cruisers and aircraft carriers under construction during that time period, that along with keel laying and launching dates, slipway capacity and other tidbits of information I've gleamed from such places as minutes from Congressional Hearings has allowed me to reconstruct which ships occupied which slipways during that time period. Nevertheless I'm always on the lookout for additional photos in an attempt to confirm if my deductions are in fact correct.

Vic


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PostPosted: Thu Jan 06, 2022 1:27 am 
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Vic,

I'm sorry I can't be of much help with matching USS MANCHESTER to a slipway. I did come across an excellent overhead view of the Fore River Yard dated 3 June 1943 at NARA. It was taken too early for either USS PROVIDENCE or USS MANCHESTER to have been had keels laid, but maybe of use. Sometimes you can compare when other ships were LAUNCHED and try to match for a ship LAID-DOWN shortly afterwards. Dick Jensen did most (all :big_grin: ) of the work in ID'ing which cruisers and carriers are which in this image.

I have uploaded a reduce sized version of the image. If this image is useful and you want the full size image, send me a PM and your E-Mail address. I can send it to you.

Image


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PostPosted: Sat Jul 16, 2022 12:27 pm 
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I would appreciate some help with USS Springfield, CL-66, as she appeared post WW2 but before her conversion.
I have the images from navsource and other sites, but cannot make out some specific details, nor can I find information about her armament and equipment during this time.

I can see there are far fewer AA guns.
I see four quad 40s amidships and I think 4 single 20mm on the corners of the superstructure. Something is in the twin 40mm gun tubs on the main deck beside X turret, and something is in the gun tubs at the stern.

There's one catapult left, on the port side, with what I think is a Curtis SC-1.

B and X 6" mounts had rangefinders, which my kit doesn't so I'll need to add. On top of all the 6" is what appear to be deflated life rafts?

Were the wooden decks painted or bare teak?

Merci d'avance at tous!


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PostPosted: Sat Jul 16, 2022 4:15 pm 
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I only have one scanned image of USS SPRINGFIELD (CL-66) taken Post-WWII, dated 9 November 1948. See attached. SPRINGFIELD was decommissioned in January 1950, and underwent several changes. The major armament change made in 1946 was moving the waist twin 40-mm mounts to the fantail quarters and deleting one catapult (these were late-WWII authorized mods to the class for Anti-Kamikaze upgrades along with improved GFCS for the 40-mm guns). Authorized 40-mm armament was four quad and six twin 40-mm mounts (four on main deck at the corners of the superstructure and two on the fantail). But, at some point the forward two twin 40-mm mounts were landed to save crew size during "peacetime". But these mounts would be returned during wartime. Number of 20-mm guns is trickier. The 20-mm mounts would be Mk 24 twin mounts, but numbers were reduced to maybe only four mounts in the superstructure. I would need to do more digging in images of sisters still in service post-WWII to locate exact locations. But, they appear to be on the deck above the main deck just forward of the bridge and higher up in the aft superstructure.

Other changes were to the radars and RCM, which would need to be specific to dates desired to model.

Decks would be bare wood and the rafts would be the same Balsa rafts used in WWII.

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PostPosted: Sat Jul 16, 2022 7:26 pm 
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Interesting photo, close range gunfire practice at anchor? Post wrath differences between individual ships became even greater than wartime.

Cheers: Tom


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PostPosted: Sun Jul 17, 2022 12:35 am 
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None of the Clevelands had rangefinders on 6"/47 turret 64 (the after most turret). The early Clevelands had rangefinders on turret 61 (the foremost turret) but these were removed (or not installed) on later ships as a weight saving measure - to allow more anti-aircraft guns.

The stern tubs have twin 40mm mounts. These stern gun tubs were a late war (or post war) addition. Not all Clevelands got these.

Phil

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