M42 in 12 minutes with the 8" F4

[NeilW]

I bought a fairly inexpensive intervalvometer from eBay and it works pretty well. Similarly, I've never tried the camera's internal multiple exposure capability. Excellent shot by the way. I have a SW BD 180mm F5 newt tucked away in a corner, and I've never used it for AP, preferring the ED80, but now you've encouraged me to give it a try...

[cometcatcher (Kevin)]

Hang on, I have tried it on manual and it does work. My memory is a bit screwy sometimes. I guess I still prefer the remote though.

[Rex]

Kevin that's an awesome shot mate. I see your getting your new toy in order. Collimation can be tricky with the F4's as you said. It took me a while to get mine like it is, and I'm still not sure it is exact. The most important thing I found with the f4 as apposed to my f5 that I have, was the placement of the secondary mirror. Took me ages to get the secondary in just the right spot so that the primary is not truncated after making the collimation adjustments. I also had some focuser tilt that a while to sort out. Your doing really well to get such detail with just 12 minutes mate, so your's can't be too far out. Great job.

[cometcatcher (Kevin)]

Thanks Rex. There's still some slight flare at the bottom of stars. It's good enough for comets but for objects like star clusters where needle point shapes are required, my collimation falls a bit short. What's really annoying is I get it nearly there, do an adjustment and I can't get it back to where it was before I messed with it lol.

Last night's comet PanSTARRS. Does a pretty good job of comets and that's what I got it for.

[andyc (Andy)]

Short subs are in fashion! Very nice Orion neb Kevin, and a great result from 12 minutes image time. I hope you can resolve your collimation issues, looking forward to more great comet (and other) images from your new toy

[cometcatcher (Kevin)]

Thanks Andy. Short subs are also good for summer with an uncooled DSLR. Helps keep the noise down.

[NQAstro (Chris)]

Very nice Kevin, now I'm getting excited i still need to get decent guiding on my HEQ5. On a side note how did u decrease the brightness of the trapezium? with my G3 CCD it completely washes out halve of the nebular. I do have an old Sony A100 but i can only use it with 100-80 ISO I might give it ago tonight and see the differences with brightness of the trapezium, Or can this be done in photoshop. I know that if I take RAW files with the DSLR I can adjust a lot of the settings. Cheers Chris

[cometcatcher (Kevin)]

Hi Chris, I take shorter subs for the trap and core and combine them in Photoshop using layers.

This is one way to do it. http://www.astropix.com/HTML/J_DIGIT/LAYMASK.HTM