DSLRMAX and Newt. focusing problem sorted!

[Keithp]

After finding out from Peter that I was getting vignetting on stacked exposures, something I hadn't realised at the time but you can see it here

http://stargazerslounge.com/imaging-image-processing-help-techniques/85312-my-first-go-galaxy.html

blatently obvious I know, but being a newbie you only pick these things up when ther're pointed out to you. So off I went and bought the dslrmax adapter.

Big problem. Can't get focus.

http://stargazerslounge.com/imaging-discussion/86694-all-set-tonight.html#post1280373

Well thanks to the engineering talent of Arthur at Ambermile :icon_salut:I have it sorted now. The first picture below shows the the original 2" ep holder with the maxdslr adapter at the rear, you can see how far it pushes the camera out from achieving any sort of focus. In the foreground is the T thread adapter on the dslr attach point on the 2" to 1.25" ep holder which I can get focus on.

So I sent the 2" eyepeice off to Arthur for some modification and essentially turned it into a very low profile 2" ep holder. The second picture shows the difference in apperture the 2" ep holder and maxdslr adapter, on the left, give you over the other method and below that you can see the new height of the modded 2" ep holder on the left.

I did have to raise the primary by about 2mm, but that's all.

Well even though last night was a disaster as regards high thin wispy cloud spoiling things I was at least able confirm it works..

Hopefully I'll get some decent results tonight.

Regards

All

Keithp

[Psychobilly]

Nice job...

Lets hope for the skies to try it fingers crossed

Where you planning on heading - M31 ?

Peter....

[Keithp]

Certainly am, I want to spend a whole night on it, the scopes pretty well pa'd and with that wider apperture I want to see the difference it can bring.

[Psychobilly]

You'll still need flats take some around dusk. set the camera to Av mode at the ISO you are going to be capturing the subs at laetr in the night grab a few... Ideally this shoudl be doen with the focus and camera orientation excatly the same as when you capture the lights but thay are better then nothing... then if you can leave the scope out till dawn take a load more again away from the sunrise ... I slew the mount around as I am taking them... my master flat is now made up from over 100 individual files...If theres any structure in the sky cover the front of the scoep with a clean white t shirt...

Bias would be useful as well 1/4000s at same ISo as lights with the scope and the viewfinder covered

Good luck

Peter...

[Keithp]

Cheers for that advice Peter:icon_salut:

I'll certainly give all that a go.

Regards

Keithp

[Milamber]

We shall see then! Crystal clear here atm, but will it last a week for Kelling?

Arthur

[Psychobilly]

Nice job on the mod Arthur

[Keithp]

heh heh, hard at work, M31 up and square this time, focus is perfect, well for a newbie.,,no banitovs here,...ooops nearly forgot it was running..

:hello2:heh heh, 6 mins and no trails

Will post up when done..this is definately a good result...for a newbie.

Many thanks to Peter for advice, and a big thank you to Arthur for the mods.

Regards

All

Keithp

[Milamber]

Cool - just the post-processing then Keith... on possibly the second-hardest target to do justice to in my book!

Arthur

[Psychobilly]

Keith whats the core looking like ... M31 is a tricky so and so and may need some shorter subs as well to control the core... concentrate on getting the longer ones first though as they will give you the detail in the outer regions...

Peter...

[Keithp]

Got some 5 minute beauts of the core, 10 at the moment all at 4 mins plus, running in and out of the last night of the proms and this georgeus blonde who can play a trumptet...ooops

back to the star gazing stuff;)

Okay so should I reduce the time and take more frequent?

[Psychobilly]

You'll need a mix really you want some where the core is a fairly tight small blob

[Keithp]

Cheers Pete, but Rule Britannia is on....hehe girl blow your bags out...give it some:hello2:

Right, back out there, cutting em down to 45 secs again

[Psychobilly]

not for long though just a few

[Psychobilly]

work up doubling the exposure after evey say 10 subs

[Keithp]

Gotcha, sheesh, just ran 8 mins and only a slight trail.

Am I looking forward to this, tomorrow:)

Okay Last Night is nearly over, running another set of 5 mins, then I'll stay with it and get 45/60 secs subs.

Did some flats by the way.

Is this where we need a chat site set up here or what!

[Keithp]

Land of Hope and Glory.....I'll be out there for real.. mean time running back and forth:hello2:

[Psychobilly]

Theres no lead for bucket loads of short ones... will be going off line soon anway to concentrate on the job in hand as the nights one and only dome tweak is not far away...

[Keithp]

Away you go Peter, good luck and thanks for all your help:icon_salut:

Posting the results in another section...and what!..........no Sea shanties.

They need their butts kickin'

Regards

All Keithp

[Psychobilly]

No probs keith lets hope we both get a decent night - the best skies all summer here probably nice view of the milkway up through Cygnus and on Cassiopea...

Domes tweaked... so might just grab an hours kip...

Peter...

[Keithp]

hmmm, remind me to get a second battery:o

Fully charged and just run out on the camera. Mount power is still good though.

Oh well off to sleep, got loads, the camera is just warming up indoors for a bit. Scope's covered over.

Beautiful night tonight though.