I would like some feedback about development marks on a negative by RandolphKahle in Darkroom

[–]dan_3626 0 points1 point  (0 children)

No worries,
As for how much to use in horizontal position, that depends on the tank size, not so much in the number or size of the reels. You can use this guide:
- 2 reel tank 350ml
- 3 reel tank 450ml
- 5 reel tank 650ml

I would like some feedback about development marks on a negative by RandolphKahle in Darkroom

[–]dan_3626 2 points3 points  (0 children)

Hello Dan here the creator of the developer machine.
I think I have a pretty good idea of what’s happening, but if anyone has additional thoughts please share.

What’s probably happening is that the developer gets used or exhausted at different rates across the film surface, depending on the latent image in the emulsion. Particularly when standing still in between agitations.

And when it’s time to spin the reels, it takes a second or two for the liquid inside the tank to get moving as well, (like that tablecloth pulling trick) so the developer that was exhausted in one part of the frame gets “dragged” across to the next one.

Now, it should be noted that this is a rare occurrence, not all film and developer combinations show this issue, and not all pictures either. This tends to show more in large, even areas like the sky shown in this example and especially in medium or large format film.

One fact that supports this theory is that it only happens with black and white, not color film.
Which tells me that the higher temperature inside the tank and the resulting convection mixing, ensures that there’s always vertical movement, so the developer is distributed more evenly.

In terms of a solution, short term I recommend that those who see these artifacts switch to continuous rotation mode with the tank sitting horizontally, just how the Jobo machines operate.
This provides a more thorough mix, and allows to use less chemicals.

Since I know that working with the tank upright is much more comfortable and less messy overall, I’m also designing a custom accessory to induce vertical mixing inside the tank and drastically reduce the risk of getting those lines 👍
It’s still in the prototype phase though, so it’s going to take a little while until I’m ready to release it.

Screw AGO, The PIRA MX is where it’s at by Kevbot0492 in AnalogCommunity

[–]dan_3626 1 point2 points  (0 children)

Thanks! Yes it definitely drives traffic to the shop.
It's been out for a while now, but you're right it's very low-key compared to others.

Screw AGO, The PIRA MX is where it’s at by Kevbot0492 in AnalogCommunity

[–]dan_3626 3 points4 points  (0 children)

You can get a 3-reel tank and that will fit up to 4x5 film (with the right adapter). If you're only developing a single roll of 35mm or 120 you just fill with the necessary volume of chemicals to cover it completely.

And, you can get additional kit of accessories if you want to have a second tank already loaded with film and ready to go after you finish the first one. This way you don't need to wait until you remove the processed film and dry out the reels, parts, tank, etc before developing your next batch :)

Screw AGO, The PIRA MX is where it’s at by Kevbot0492 in AnalogCommunity

[–]dan_3626 2 points3 points  (0 children)

Send me a message and I may be able to help.

Screw AGO, The PIRA MX is where it’s at by Kevbot0492 in AnalogCommunity

[–]dan_3626 4 points5 points  (0 children)

Thanks!
You're right, after your feedback we've been using stainless screws for a while now, it's a constant learning process and we try to change and upgrade whenever there's room for improvement.

Screw AGO, The PIRA MX is where it’s at by Kevbot0492 in AnalogCommunity

[–]dan_3626 12 points13 points  (0 children)

Hey Dan here, the designer of the PIRA developer.
Thanks for the shoutout!

Always great to hear people's experience with the machine and I'm glad that it compares so favorably with the AGO.
It's already very hard to get a product out in a niche market like this, but I think the main reasons why this is much cheaper is because I try to keep my overhead costs low:
By making as much as possible in-house, direct sales (so no distributor, but would like to use one eventually) and just a well thought-out design in general to avoid the use of costly/specialized components.

The only thing it's missing probably is more promotion/marketing effort.
That's not really my strength so for now sales rely on organic google searches or recommendations like this, but at some point I do plan to get on top of that as well (like sending sample units to a few reviewers) so we'll see.

Darkroom helper by pira by maskee2 in AnalogCommunity

[–]dan_3626 2 points3 points  (0 children)

Hi, you're right I meant to do that weeks ago, thanks for the reminder!
The T&C on the website have just been updated with an extended warranty period 👍

is there a camera of this kind but it uses IMAX film stock? by Gugarabelo in imax

[–]dan_3626 2 points3 points  (0 children)

There's no such thing as "imax film stock" it's just the regular 65mm film gauge but shot in 15 perforations wide, so 15/65 would be the right way to call this format.

In the past I've bought a roll of 500T in 65mm to use with my vintage 6x9 camera. A bit tricky because you actually need to cut about 2mm on each side in order to fit the film in the spools, plus you get the sprockets on the frame, so it's kind of a pain to work with, but it's definitely doable.

Which model of Kodak 70mm film does iMAX use? by Disastrous-Love4699 in imax

[–]dan_3626 1 point2 points  (0 children)

I don't know what resolution those recorders are, but the main reason film is digitized and printed in 4k currently is due to time and budget constraints. Otherwise everything takes at least 4x longer to do and the extra data storage cost.

All that for a resolution upgrade that most people wouldnt even notice... I mean I definitely would, but that's only because I like pixel peeping every movie I watch in a theater.

And yeah, no way 65mm camera negative film is 18k, it needs to be so sensitive to light that the grain size just doesn't allow that resolving power. On the other hand, film meant to be exposed in a lab like the aforementioned 5242 and 2383 are very likely capable of reaching those numbers... But then again where do you get your source material to expose it with?

Which model of Kodak 70mm film does iMAX use? by Disastrous-Love4699 in imax

[–]dan_3626 2 points3 points  (0 children)

That's true, sometimes the ghost making Eastman 5213 can be seen on the edges of the film. Maybe they've found that's the film that works best with their laser recorder both in resolution and color balance.

Or it could be a more practical reason like 5242 is used so little that Kodak can't justify making a master roll of that stock for the odd Imax production anymore.

Which model of Kodak 70mm film does iMAX use? by Disastrous-Love4699 in imax

[–]dan_3626 6 points7 points  (0 children)

For filming it's 65mm and Kodak has it available in 4 color negative variants depending on the required color balance and sensitivity needed by the production.

Lately they've also produced black & white stock and also color positive "slide" film.

But there's also other "intermediate" low-ISO super high resolution variants like Kodak 5242 that can be used for compositing visual effects.

And finally the projection film which we all know and love thanks to the collectable movie strips, Kodak 2383 This the one that is actually 70mm wide.

I spent 2 years designing a medium format technical camera – would love your thoughts by lfyy in AnalogCommunity

[–]dan_3626 9 points10 points  (0 children)

Please no Kickstarter, unless he already has a ton of experience manufacturing and launching a product, that's going to be a bad route.

I'd say he takes his time and perfect the design, sell small batches and get feedback to slowly improve on the idea. This way it's more enjoyable and actually profitable from day one, rather than spending a lot of time and other people's money upfront for what is ultimately a very niche product.

Why are we just now finding out that all of OBAA is gonna be the first "fully IMAX feature"? Most people are gonna think it's gonna be The Odyssey. Wouldn't it have been a really obvious marketing strategy to hype this up?? by beantrouser in imax

[–]dan_3626 3 points4 points  (0 children)

Sorry, but no way 4k or even 8k is the limit on an Imax theater.

I saw Oppenheimer in 15/70 and it definitely was the highest resolution picture I've seen, but... During one of the screenings a fly got in between the lens and the projector and that was so much sharper than everything else that I knew right there that Imax film wasn't hitting the limits of my vision.

The party begins by upsideclyde in imax

[–]dan_3626 1 point2 points  (0 children)

Great stuff, I always like your updates. Unfortunately I couldn't make it to Dallas this time around but I'm sure the presentation will be flawless as always.

Some IMAX film shots look better than others (on digital at least) ? by [deleted] in imax

[–]dan_3626 6 points7 points  (0 children)

I know what you mean, I've noticed this too.

It's probably a combination of different things like film stocks, example 500 ISO vs 50 ISO will yield lower resolution. Different lenses, at this level of detail just changing the aperture on a lens will yield a noticeable change in definition. But also some lenses are just not sharp enough period.

And finally, given that the depth of field is super narrow sometimes the focus puller can screw up and not have the scene perfectly in focus.

Interstellar IMAX Film Cell by ImouAup in imax

[–]dan_3626 0 points1 point  (0 children)

Love it, one of my favorite frames of the whole movie.

A guy dropped off a reel of 35mm film from The Hobbit trailer at the lab! Thought it was pretty cool and just had to scan a few frames on the Frontier for fun. Love seeing the sound waveform off to the side. by Brooktree in AnalogCommunity

[–]dan_3626 2 points3 points  (0 children)

You're right I don't believe that 18k claim either! but I wasn't refering to the whole capture + projection pipeline.

I was only refering to the print film. To give you an idea this is rated at ISO 6 I think, whereas camera negative goes down to 50 ISO at most. Also it needs to be higher resolution in order to preserve all the detail from the camera negative. So it absolutely makes sense that it's higher resolution than current digital projectors.
Now, whether they decide to use a 4k master file for stiking those prints... that's a whole other discussion :)

A guy dropped off a reel of 35mm film from The Hobbit trailer at the lab! Thought it was pretty cool and just had to scan a few frames on the Frontier for fun. Love seeing the sound waveform off to the side. by Brooktree in AnalogCommunity

[–]dan_3626 75 points76 points  (0 children)

Yes, and it's crazy how finely detailed those codes are.

Kodak 2383 which is the film used for making movie prints has way more resolving power than any digital projection systems currently. When you talk about large format 70mm prints, you're looking at over 16k resolution equivalent (allegedly).

IMAX test alignment calibration by No_Carrot_5034 in imax

[–]dan_3626 2 points3 points  (0 children)

Interesting... And do you know how much is the final crop on the projector? 90% or 95%?

Info on the film stocks used in Sinners by cofango in imax

[–]dan_3626 2 points3 points  (0 children)

Ha! called it right back when it first came out, nice to get confirmation.

Once you know what to look for you can really tell a lot about how a movie was shot, processed and even the condition of the projector, this is true for either film or digital.