a7s star eater with M33?

[photoncraft]

Hi..

I shoot M33 some days ago with my sony a7s. and i wonder star eater issue are exist. 

Set the shot as bulb mode, iso 6400, and 123sec exposed.

Celestron 8" and advanced VX with Orion SSAG.

I attached original jpeg file. what about your think compare with your experience? 

thanks

[happy-kat]

When you are next set up on the same target if you took a 30 second exposure or even a 29 second and a 40 second as well and then compared those to the above image. Even comparing the three new images to eachother may help know what is happening.

[alacant]

19 minutes ago, photoncraft said:

hat about your think compare with your experience? 

Hi. Excellent. A single 2 minute frame with that amount of detail is very good. What you can do is take many more 2 minute frames and stack them. Maybe go to 4 or 5 minute frames to get even more detail but take RAW frames rather than .jpg. HTH and clear skies.

[mikeyj1]

for a 123s exposure, it seems pretty reasonable.  You can see some Vignetting in the corners, and noise in the image, but for a Jpeg single image stars are nice and round detail and colour is coming.  

Suggestions:  change to RAW if possible, stack multiple image, add 'dark frames' (deep Sky Stacker is free) and get a copy of making every photon count or similar beginners astro-photography book.

Welcome to the forum

[photoncraft]

thanks for all reply.

as all reply, it looks a7s star eater issue are gone now. i tested 30sec over, or bellow, no deferent. 

however, when i turn on silent shooting, the problem happens.

originally i shoot as RAW and uploaded picture is just jpg for reference. i uploaded stacked works.

this stacking is all 6X180sec/3200, 5X120sec/6400. stacked in Affinity photo. no dark,no vias, no flat.

thanks again

[fwm891]

That's better - the more sub frames you add the deeper the image goes. You could be clipping the blacks with this image too which won't help.

[alacant]

1 hour ago, photoncraft said:

no flat.

Add flat frames and you'd be onto a winner:)

[photoncraft]

Thanks suggestion fwm891 and alacant. anyway i'm happy that confirm a7s shoot with bulb would have no eat star  issue anymore.

[happy-kat]

This has a little background to help you know whether or not you experienced it. link here though it sounds like you are not :)-

[sharkmelley]

Your Sony A7S will definitely have the star eater in bulb-mode exposures because Sony has not released any firmware update that switches it off.

However, it's only a problem for very tight stars.  A Celestron 8" scope is a long focal length and will produce relatively large stars which are relatively free of star eating behaviour.

Mark

[photoncraft]

Thanks happy-cat and sharkmelley. it looks more sharp stars need serious update from Sony. my focal length is beyond recognize small stars which occurs eating. 

Thanks for information.