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Late to the party, but Ektachrome is coming back!

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#101 Michael Covington

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Posted 14 June 2018 - 03:11 PM

Focusing is indeed an issue.  With a digital camera, we can preview the actual sensor image, magnified, and be sure focus is perfect.  With film, we have to trust the SLR to be accurate and the film to be flat.



#102 Faintandfuzzy

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Posted 14 June 2018 - 05:31 PM

I have thoroughly reviewed what Ken did, and can find no errors.  How about some objective analysis of your own and how does it conflict with what he did?

Ken's results on not based upon testing.  My results are.  If one even tests with a high rez airforce test chart, you will not achieve anywhere near the figures he is posting.  His figures are based upon nothing more than scan size.  This has been debated to death in photo forums...Ken is wrong. 

Here is a sample of an 18mp DSLR vs film.  Film barely hangs on at 18mp....let alone Ken's figures of over 100mp.

 
IMG 6238


#103 Alen K

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Posted 14 June 2018 - 10:14 PM

Roger Clark works on digital cameras and sensors for NASA and has been doing photography at a professional level for decades. Sounds like (relevant) credentials to me. Granted, that doesn't make him right. Whether one has credentials or not shouldn't have any bearing on the validity of an argument or the data they present to make it. 



#104 SandyHouTex

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Posted 22 June 2018 - 09:06 AM

Ken's results on not based upon testing.  My results are.  If one even tests with a high rez airforce test chart, you will not achieve anywhere near the figures he is posting.  His figures are based upon nothing more than scan size.  This has been debated to death in photo forums...Ken is wrong. 

Here is a sample of an 18mp DSLR vs film.  Film barely hangs on at 18mp....let alone Ken's figures of over 100mp.

You did read the article, yes?  In the first post it’s under the heading “Digital Resolution”.

 

Your results are not that important because I don’t know your test conditions, assumptions, test set-up, or anything.


Edited by SandyHouTex, 22 June 2018 - 09:10 AM.


#105 SandyHouTex

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Posted 22 June 2018 - 09:11 AM

Roger Clark works on digital cameras and sensors for NASA and has been doing photography at a professional level for decades. Sounds like (relevant) credentials to me. Granted, that doesn't make him right. Whether one has credentials or not shouldn't have any bearing on the validity of an argument or the data they present to make it. 

Credentials are everything.  See my post above.  There are too many “internet experts” who do things and think that they are an expert because of it.



#106 Michael Covington

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Posted 22 June 2018 - 01:48 PM

What someone needs to do is photograph the same subject (astronomical or terrestrial) with the same lens with a modern digital sensor and with film, then compare the results.  Magnify the film image with a microscope rather than scanning the slide or negative; otherwise the scanner is the limiting factor and is likely to be quite similar to the digital sensor it's competing against.

 

Bracket exposures widely because it will be hard to tell in advance what is a good match.  Even bracket the focusing with film (move it slightly to either side of the position that gives sharpest focus on the SLR screen) just in case the SLR is misadjusted.  Take the sharpest film image and the sharpest digital image that are of comparable brightness.

 

Is anyone up to doing this?  I've put it on my list of things to do eventually.



#107 Faintandfuzzy

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Posted 23 June 2018 - 10:44 AM

You did read the article, yes?  In the first post it’s under the heading “Digital Resolution”.

 

Your results are not that important because I don’t know your test conditions, assumptions, test set-up, or anything.

Yes, I have read the article.  And I know Ken as well.  Having been a photographer for more than two decades myself, I am no stranger to testing thanks.  These tests were done with a Nikon F5 and a Canon 7D.  Some of the film was scanned on a Nikon 9000 scanner, some on a Minolta 5400II, some on a Howtek Drum scanner, and finally on an Imacon 848.  Top glass was used on both, both were tripod mounted.  Even with the Imacon at 8000ppi, there was simply no more detail to pull from the scans. 

 

To tell someone that their test isn't important simply because it disagrees with you is a rather odd approach.  Film simply runs out of steam on standard contrast subject matter.  But even using high rez test charts, using films like Provia, Ektar, TMax, etc, you will not see more than about 20-24mp of real detail. 

 

People like myself use film professionally because of the different look.  It has nothing to do with resolution for 35mm.  That I'm afraid is not open to debate.  


Edited by Faintandfuzzy, 23 June 2018 - 10:46 AM.


#108 SandyHouTex

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Posted 04 October 2018 - 09:49 AM

So I guess Kodak was just pulling our chains about Ektachrome coming back.


Edited by SandyHouTex, 04 October 2018 - 09:49 AM.


#109 TxStars

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Posted 05 October 2018 - 02:31 PM

WOOOOOOT

 

https://www.freestyl...m-x-36-exposure



#110 SandyHouTex

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Posted 05 October 2018 - 05:47 PM

I just checked bhphotovideo.  They’re allowing preorders with an expected availability of mid-October.  I couldn’t be happier.



#111 SandyHouTex

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Posted 14 October 2018 - 09:45 PM

BHPhotoVideo and Adorama are shipping Ektachrome now.

#112 apollo16uvc

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Posted 06 May 2020 - 11:03 AM

Ektachrome has since also been released in 120 rollfilm and 4x5 sheet film.

 

Here is the spec sheet For E100: https://imaging.koda...achrome_100.pdf

 

From my personal experience, using Nikkor AF-S primes and slow speed (Ektar 100, Portra 160, Velvia 100) with a nikon super coolscan 9000, film has a resolution of 4000DPI.

 

You may be able to get more if you use Leica or Carl Zeiss optics and 20-50 speed film.

 

But at that point, manual/automatic focusing and  lens resolving resolution becomes much more critical than the film... and to go beyond 4000 DPI your only option are drum scanners, hasselblad flextight scanners of medium-format digital bodies.


Edited by apollo16uvc, 06 May 2020 - 11:05 AM.


#113 Michael Covington

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Posted 06 May 2020 - 09:50 PM

Let's see... 4000 DPI is 160 dots per mm, or 80 lines per mm.

 

Sounds exactly right.

 

I would say it corresponds to a pixel size of 1/80 mm = 12.5 microns (about 3 or 4 times the size of a DSLR pixel), but there's another difference.  The point spread function of film is gradual, so the resolving power depends on contrast and is usually measured on high-contrast subjects.  On subjects of average contrast, it's lower.

 

I have long felt, from rough experiments, that film is about 1/5 as sharp as a 24-megapixel APS-C DSLR.  That's quite close to the same conclusion. 

Of course you can get film with bigger sensors!  Full frame 35mm up to 4 x 5 inches.



#114 apollo16uvc

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Posted 07 May 2020 - 04:34 AM

Now, the exception to this are super low speed film 

 

Adox CMS II 20 has a resolution of 800l/mm

 

http://www.adox.de/P...-ii-adotech-ii/

 

And when scanned at 8000DPI, i have yet to see grain. Those SCALA-processed slides are really in their own league.

 

However, i do not believe there exist optics on this earth that can resolve 800l/mm.  Most cap out at 100-200l/mm. 

 

Acros 100 and tmax100 ccap at something like 120-150l/mm


Edited by apollo16uvc, 07 May 2020 - 10:25 AM.

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#115 apollo16uvc

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Posted 07 May 2020 - 03:15 PM

120 Fuji Pro 160S

Mamiya M645 w/ Mamiya 80mm f4 Macro

Nikon Super Coolscan @ 4000 DPI.

Flickr link

59mp 120mb download.

 

 

Adox Silvermax 100

Pentax Spotmatic w/ Pentax 50mm f1.7

Nikon Super Coolscan @ 4000 DPI.

Flickr link

24mp 17mb download.

 

 

Kodak Pro100

Nikon F100 w/ mamiya 645 300mm f5.6

Flickr link

24mp 18mb download.

 

But again, at 4000 DPI the manual-focusing skill of the photographer is by far the most critical aspect. I believe even AF on my F4 and F100 would fail to nail the focus at this point.

 

 

Yes digital has far surpassed 35mm with 42mp bodies and is better in conceivable way. But medium format is still something else, and most people shoot film for the texture/feel anyway.

I partially shoot it because those heavy, manual focus bodies are just so **** satisfying to use!


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#116 luxo II

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Posted 18 June 2020 - 06:48 AM

I shot a lot of astrophotography in the 80's and 90's, some on Ektachrome. I used two approaches either Ektachrome 64 and went for longer exposures ~ 20 minutes to 1 hour, or the ISO400 stuff for short exposures (5-10 mins max) and pushed it another 2 stops in processing to ISO1600.

 

With both the reciprocity failure was savage and with some experimenting you will find there is a limit to the exposure time where longer has no benefit.

 

There is a way to defeat the reciprocity failure - using a cold-camera - in which the film is sandwiched behind a thick glass plug, with a metal back chilled by dry ice.  The glass plug being necessary to stop frost forming on the film, which also has to be pre-cut into single frames because at that temp it is brittle and tends to break. I only knew of 1 guy who actually used it and even then with the time to get it all set up and ready, he might only manage 1 shot in an evening - only to find afterwards the focus was off, or the glass plug fogged... etc etc... a lot of frustration for  very few results.

 

Film is perhaps interesting for those young ones who never experienced the magic of it, and doing your own developing, making prints and perhaps having a go at unsharp masking is a very valuable experience. But very costly and time consuming, per frame.

 

Like vinyl records its time long has passed.


Edited by luxo II, 18 June 2020 - 07:00 AM.


#117 astro744

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Posted 20 June 2020 - 08:01 PM

To overcome reciprocity failure, I used hypered film which I bought from a specialist supplier when needed.  I never got around to buying the Lumicon hypering kit.   The first time I used hypered Kodak Tech Pan 2415, I overexposed the Sagittarius region!

 

See http://www.astropix....m/hypering.html for a description on hyper-sensitising.

 




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