Testing the Astrophotography Waters....

[THXGEEK]

OK, so I had a few minutes decided to target Orion. Set up my A7CR on the tripod with my FE 20mm 1.4. My settings:

Full manual mode.
ISO 500
F1.4
5 seconds
10 second delay after hitting the trigger.

M42 is plainly visible, but I think overall focusing is still off a bit - I am using focus peaking, zooming onto a subject star and adjust until its a small red dot. Shoot.

Any suggestions to help with focus and exposure?

• ILCE-7CR
• 24.0 mm
• ƒ/1.4
• 5 sec
• ISO 500

 

[DaveC Oz]

Hi Craig. I generally set my A7CR to 6-8 second exposure times with a higher ISO. Generally I will take a few shots at up to 16000 ISO just to confirm composition and focus. Then I dial back my ISO to achieve better exposure. For focus I use magnification only, for me I find focus peaking to be distracting, and also not very helpful on wider angle lenses. It's also important to switch lens and camera stabilization off. I actually no longer use a delay for triggering my shutter, it was explained to me that, as long as the tripod and camera were stable, then the fraction of time that pressing the shutter caused movement, in the context of a long exposure, was so small that it didn't show on the photo. Experiments have backed this up. If you haven't already stumbled across his videos, I would recommend the late Alyn Wallace's You Tube videos as well. Welcome to the Dark side of photography, unfortunately being on the Eastern edge of North America finding really dark skies may be quite a challenge. Good luck, and clear skies, to you, if you want to bounce any ideas around feel free to contact me, I've only been playing with astro a couple of years but it has taught me a lot.

 

[FowlersFreeTime]

Not bad, what is the bortle rating where you took the photo?
By the way, I believe the A7CR has the same rear screen & EVF as my A6700; if so, focus peaking will likely get in the way. I agree with Dave, use magnification only when focusing.

 

[THXGEEK]

Gents -

Thanks for the feedback - much appreciated!

OK, I'll disable the focus peaking and try it again. I've also read that a small 10x standing loupe will help to get the last few pixels of focus out of the rear display - I may try that as well.

Confirmed, all lens/camera stabilizations are turned off.

Will definitely check out Alyn Wallace's You Tube videos.

Annnd, sadly, I live in the suburbs of Northern Virginia. My Bortle rating is 7. I've considered asking the folks at Dulles International airport shut down for an hour or two when the night skies are clear but doubt that will go anywhere. And will someone please turn off the Moon? Sheesh!

Cheers,
-- Craig

 

[DaveC Oz]

Gents -

Thanks for the feedback - much appreciated!

OK, I'll disable the focus peaking and try it again. I've also read that a small 10x standing loupe will help to get the last few pixels of focus out of the rear display - I may try that as well.

Confirmed, all lens/camera stabilizations are turned off.

Will definitely check out Alyn Wallace's You Tube videos.

Annnd, sadly, I live in the suburbs of Northern Virginia. My Bortle rating is 7. I've considered asking the folks at Dulles International airport shut down for an hour or two when the night skies are clear but doubt that will go anywhere. And will someone please turn off the Moon? Sheesh!

Cheers,
-- Craig

Just for further information, I've yet to find the person at the weather bureau to pay off for cloud free skies

 

[THXGEEK]

Just for further information, I've yet to find the person at the weather bureau to pay off for cloud free skies

Well, as it turns out, I am a certified SkyWarn Observer for our National Weather Service (Yes, I am also a ham radio operator - so many hobbies, so little time!) and have the contact info for the lead meteorologist at our local NWS office. I'll give him a shout and see what he can do! With any luck, he'll have some connections Down Under - I'll put in a kind word for you!