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jahnpahwa
18-03-2021, 02:37 PM
I recently dug out a couple of old film cameras and ran a roll of Ilford HP5 through one to see if it was still working. It seems fine, and with the correct batteries the metering seems about right too.

I found a bloke on cloudy nights who was able to send me a T-ring for these cameras, and am looking forward to what I can show (of Carina perhaps?) with a sensitive film loaded and a long single exposure.

This is the moon over the Murrumbidge valley, just outside of Canberra... actually, I think the fields you see are in NSW around Wallaroo.
Olympus OM2n, Zuiko 50/f1.8 at f16, Ilford HP5 handheld

The fun I've had over the past few weeks with film, going places to shoot and having the kids come along with the digital cameras has shown that its much more (young) family friendly than astro, so I've offlaoded a scope and some other gear and picked up a bigger camera that will hopefully bring some good landscape results.

I wonder if anyone here shoots film for astro anymore?

Sunfish
18-03-2021, 06:45 PM
Interesting. I have thought of it. I have my sons medium format camera lying around and some film. To reduce the cost of errors one could use BW film developed at home and RGB filters , then scan the film and combine. Problem is working out focus unless you have an identical digital body or can do knife edge focus on the film body.

jahnpahwa
19-03-2021, 10:47 AM
Yeah, focus through a scope will be tough, maybe a bahtinov will be visible? I don't know. That will be the OM with 35mm film.

I will put the medium format on top of the newt and guide it. The lens it comes with (100mm) creates a field about the same as a 42mm on a full frame sensor, but the negative (6cm X 9cm) should scan and be sharp well beyond any consumer digital sensor (300+mb TIFFs without going too hard on scanning). The fastest colour 120 film I know of is 800, which should get some decent results at f3.5.

Sunfish
22-03-2021, 03:51 PM
I have a Pentax film camera and also a digital camera. So I should try that, focus with the digital and then swap to the film.

I do not think you will see the Bahtinov diffraction on the optical viewer but perhaps with the medium format and a loupe on the focus screen that would work. Unless you find an old stiletto or mitsuboshi knife edge focuser somewhere.

Mickoid
28-04-2021, 05:29 PM
I like your idea, should still work using that technique on a 35mm SLR provided there are some bright stars in the FOV to focus on. RGB filters are normally parfocal so once you've focused through one, usually the green filter because it's the brightest, the other two should be in focus, provided nothing moves in between exposures. I think from memory Ilford HP5 is 400 ISO but can be pushed in processing 3 stops if you calculate your exposure based on an ISO value of 3200. I shot the Carina nebula on Konica 3200 ISO colour film about 30 years ago and at f10, I needed an exposure of 30 minutes. You may need more time than this using HP5 B/W film and RGB filters, depending upon your working focal ratio. The blue filter will be the extra long exposure using film. Good luck! ;)