How to shoot desert with many stars in the sky?

[Evgeny]

My experience is that you will get noticeable star trails if you expose for longer than that. Of course this may or may not be a problem.

Sure, 28 seconds - is the longest exposure without star trails with 35mm f3.5 Contax 645 lens.

This is a religious argument for visual observers, but for photography, GPS doesn't solve the problem by itself---you still need an equatorial mount aligned to north to track the movement of the sky without causing apparent rotation of the visual field.

Well, this was my assumption. I have no experience with GPS and fork (?) mount, but precise alignment of Equatorial mount in the field is not easy if ever possible for very long exposures without hand corrections.

 

[poutnik]

Neil Folberg shoots 2 completely separate exposures on different film, merges them digitally. That's the description in the interview.

 

[Evgeny]

Jiri, thank.

 

[Evgeny]

I will be approx 24 hours in the desert close to Dead Sea in Israel.
I believe there is a high lever of salt in the air there.

I will take a Contax 645 with a film back for night long exposures. I think to take another Contax 645 with Sinarback 54M and Macbook for Sunset and Sunrise.

How would you protect the equipment in the Dead Sea desert area?

Thank

 

[Evgeny]

I'm back to home.

It was 40C/104F degrees at 8PM. I shoot one 120 roll of Velvia 50 and we quickly tired. In the early morning I shoot 6 frames of Astia 100 of Sunrise, the temperature was 32C/90F. The Sun was so bright that we decided to go home after half an hour.
I will develop slides, scan and post in September. Not that quickly.

 

[daleeman]

I remember reading about a formula that takes into account the lens length, film speed and F stop as to how to capture with no streaks, and with a predictable amount of streaks. But... I can not find where on the ever so huge Internet it is posted. Does anyone know where these discussions are?
Lee

 

[Q.G.]

You haven't tried very hard, have you?
First (!) hit in Google, using "star trail formula".

 

[Evgeny]

Thank, will use next time.