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peeb61
03-10-2014, 03:56 PM
The Mylar arrived and it was quickly put to use.

This is the first light, I know the focus is off a bit and the Sun was setting but what are the streaks? On the first image? Is it because the Mylar is not flat enough in its housing? I read here somewhere it doesn't actually need to be perfectly flat? Or am I wrong? I have uploaded a second image and with a little bit of processing the streaks are fainter? Should I be capturing at a slower rate?

Anyway your thoughts would be a great help.

Both images taken at 1/200 sec.

Many thanks

Paul

Merlin66
03-10-2014, 04:12 PM
Paul,
The streaks are not coming from the solar film.
Yes, you are correct the film should not be pulled tight, a bit of "waviness" is OK.
Which camera were you using?
I'd suggest smears on the glass cover of the chip (unless you have a filter in the optical train ...)
Your exposures look OK - the faster the better - to control seeing.
Good start....well done.

peeb61
03-10-2014, 04:20 PM
Thanks Ken, I am using my QHY8L camera to take the exposures, I will check the glass filter on the camera for any contaminants, I didn't think of this. :thumbsup:

Should I be using a DSLR? or stick with the QHY?

Many thanks for a quick reply.

Paul

Merlin66
03-10-2014, 04:25 PM
At this stage either will probably give good results.
To get maximum results you'd have to consider a fast frame webcam type - preferably mono.
I use a DMK41 and DMK51 stacking 400+ frames for good results. (Both in white light - Baader wedge or Ha - 102mm PST mod +SM60 etalon.)
Hope this helps,

peeb61
03-10-2014, 04:37 PM
Ken, My 500D has movie mode would this be sufficient enough?

Paul

Merlin66
03-10-2014, 05:52 PM
Probably worth trying....but I believe the frame rate may be too low (I've seen 10 frames/ sec mentioned)