God give me strength, any God!

[Fay]

Set up early , last night, to iron out any problems!

Decided to use WO with FR & cls filter. Was just short of getting focus with cls filter, as I have to use a tube. So, it was either, no,FR or no cls. I decided I needed both & switched camera's around.
Getting darker now, so panic setting in.


Set off ok, had to watch the paint dry for hours, as scared to leave it. Suddenly, image that should be 600 sec opts out at 240, so have to delete, next image starts regardless. Battery had gone, usually DSLR Focus shows a gradual decline, but this time it did not. Changed everything. Got to darks & have not yet found out where they have gone. Everything seemed to working ok, but where are the darks???????? Changed battery again, did flats.

I've looked everywhere but they did not download, sat there at 1.30 searching to no avail.

If I felt in a good mood, I would blame the fox!

Fay
 

[Fay]

Something else I have thought of.

The other night, one of my 600 sec subs, looked darker than the others. I think that this opted out before time, but the file extension still shows 600secs. 

Also, last night two of my light subs did not download.

[RobertM]

Are you answering your own posts again

[Fay]

Yes, I'm going insane, Robert. I have processed the image & it is rubbish. All those hours!!!!

Lot of amp glow lower right, too may stars, & on zoom the colours are streaked. Will show you tonight, if there is time.

Did you do anything last night?

[RobertM]

Sorry to hear that Fay, it looked like a very good night last night too.  I got some sleep but will be going to hear what Mark has to say tonight then if it's clear I'll do some imaging after using a proper cooled camera...

[MarkS]

Fay,

I'd like to see what you mean by streaks in the colour.  I have seen streakiness myself.  It was caused by  hot pixels and pixels that are almost hot creating a streak effect during stacking.  It occurs when these noisy pixels are overcorrected or undecorrected i.e. because the darks are not properly matched to the image.  This is either because the darks are taken at the wrong temperature or because they used the wrong exposure length.

You said some darks cut off early.  This might explain it.  In my experience exposures are sometimes cut short when the battery is losing power - holding the shutter open is very draining for the battery and they can give up before the scheduled exposure end.

Mark

[MarkS]

Fay,

Forgot to say - to counteract the streaks try sigma stacking (it's an option somewhere in DSS) if you are not doing so already.  Try sigma values in the range 1.0-3.0 and see if it makes any difference.  It may well help but it's not a complete solution.

Mark

[Fay]

Thanks Mark. Mark, what does that registration of stars bit mean, where you can alter the % of shown stars?

I will post the image so you can have a look.

[Fay]

DSS only accepted 5 subs, I know there are not nearly enough but even without the darks I think it should be a lot better than this.

[Fay]

Yes, I did do darks Mark, but they never downloaded. If the software had warned me that the battery was low, it may have been a better outcome. Perhaps I should try downloading to the card? But I will check after each sub to see if it is there.

[MarkS]

Fay,

The coloured streaks are hot pixels - darks would have helped.  Go to a cool room and create some darks now - they won't be perfect because the temperature will be slightly different but they will help enormously.

Change the % until DSS finds approx 50-200 stars in the image.  That ought to help it to stop rejecting so many subs. By the way - you said it accepted 5 subs - how many was it rejecting?

I think DSS will be able to do a much better job once you provide it with some darks. 

I prefer my camera to write to the card - there's FAR less to go wrong with that approach.  Maybe I'm just a Luddite!

Mark

[Fay]

It rejected 2 subs but I lost two, they never downloaded. I had 8 or 9 in the beginning. I am wondering if I could have had the FR in a different place. When I put it on the WO the vignetting was awful.
It is so long since I used the EOS that you forget the right combination of putting the bits together.
I thought you should put the FR as near the chip as possible?

[Fay]

I did that Mark, but it still rejected 2 of the subs. I did  some darks & also stacked a different way, but will have to give it up as a bad job

[MarkS]

Don't give up!

I'm positive Iris can do it!

[JohnP]

Fay - I said I thought that this was brilliant... not quite sure why you didn't post it earlier. The detail is unbelievable & focus looks spot on. I can only guess the defraction spikes came from something holding a lens somewhere in the optical train they must be on the original. I don't think DSS has option to add diffraction spikes???

John

[MarkS]

Fay,

I didn't know you could hire time on the Hubble Space Telescope!!!   

[RobertM]

Nice picture Fay, it's got a little to much detail for my liking though...

[Daniel]

Wow, that's gorgeous think that might be my next target, though doubt I'll get anywhere near as good as that love the contrast!

[JohnP]

OK Fay - So you've 'fooled' me... & I've even admitted it on a public forum....

[Fay]

I don't know whether to laugh or cry! I have a confession.

I redone & rotated my Pelican image, I deleted all subs & other images of it as I had had enough of it. The cropped pelican was the only one I kept, so I could see the best position to put it when I do it next.

I download professional images for my desktop, & somehow this one has got into the wrong folder. It was the only one there & I thought it was mine......not bloody Hubble's!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

I thought it did not look so bad & am cheesed off that it was not mine, God knows how it got into my Canon folder. I thought it was suddenly looking not so bad. John it was not deliberate I am in a state of shock.

[JohnP]

Fay - I'm in a state of shock that I actually thought it was yours.....!!!! 

[JohnP]

oh dear Fay - You've posted it on UKAI !!!!!!!!!!!!!!! Good luck getting out of it......

[RobertM]

Fay, I feel very sorry for you and your mixup but whata mistaka to maka ...

Expect a call from Russell Croman and Nick Syzmanic asking for advice and time on your telescope now ... you may achieve god like status briefly 

[MarkS]

Fay,

That's an incredible mistake to make!  Once you're over the shock this is a story that will remain in the annals of history ...

You'll look back and have a really great laugh about it!!!

Mark

[Fay]

I have just rung Ian King regarding bunched up stars in the corner of the Pelican.

I appears that the WO 0.8 fr/flattener will not be ok with the ED80/EOS setup, because the chip is larger than the SX & it was only designed for Focal Length of around 380mm. The ed80 is around 600mm.
The same as, the 0.25FR is only ok for webcams's etc & not the SX, because of chip size.

There will be vignetting with the 0.8FR, WO ZS66/ EOS/no room for cls filter, as direct coupling, because of chip size. Not sure if I noticed that before. Flat field should correct that. (I think I only used it in Tuesnoad) & did not need cls filter

When I used EOS/FR/2" tube, cls, WO ZS66, I could not get in close enough to focus on star. It was suggested buying a clip in cls filter, that you have, Robert, but leaving the 2" extension tube off.

The bottom line, as usual spending more money, was, a WO mk3 fr/flattener suitable for 600mm fl, £149, for the EOS/ ED80 setup.


Fay

[RobertM]

Hi Fay,

The reason I got the clip filter was just that, it takes up no back focus and can also be used with camera lenses.  I also had to get a short canon-2" adaptor (truetek) to ensure the correct corrector to chip distance (+/- 1mm) with the Reducer Corrector.  Will find out whether it works sometime soon but at the moment I'm happy just using 200mm lens.

Robert