Problem with inwards focus on a 250px using spc880 webcam

[spaceboy]

I think we have an understanding now though

As I was aware Madhatter has the newer scope I naturally thought that it would fit OK but as you so rightly pointed out if he has on the off chance got the older focuser ring it may not work. I guess it wouldn't hurt just to check the draw tube diameter just to make sure.

[Madhatter]

Thanks for your help guys:) i have checked and i have the same focus tube as spaceboy, my scope was bought back in june this year so i think its a newer one.

I tryed barlowing the webcam when i finaly got a gap in the clouds, but to no help at all, couldent even get close to focus even with the barlow, so i think (fingers crossed) a scopeteknix adapter should solve the problem! just of to order one now:)

[spaceboy]

I'll be interested to hear how you get on as I'd planned to have a go using my 250PX on Jupiter. If the skies ever cleared here that is

[Madhatter]

will keep you posted mate;)

ahh tell me about it, its been a complete nightmare here recently! has this year been particularly bad for astronomy? since i got into it back in april i think there has been a total of around 15 nights of good viewing:confused:

[Stephen]

If you can't focus with the Barlow, I'm confused

A Barlow will push the focal point out (away) from the focuser - it should be easier to focus with the Barlow than without?

Is it inward or outward movement you are short on (with the Barlow?)

[spaceboy]

will keep you posted mate;)

ahh tell me about it, its been a complete nightmare here recently! has this year been particularly bad for astronomy? since i got into it back in april i think there has been a total of around 15 nights of good viewing:confused:

We have had some clear nights here but there has either been a full moon high in the sky, a high level haze, an insane amount of dew in the air or an early morning of commitments making a nights sleep essential. If I'm honest I can't remember the last time I had a good nights observing. The peak star party was the last time I can say I have seen any thing but even then there seemed a haze high in the sky on those nights.

[Madhatter]

I can remeber to be honest mate, but i definitely could not and i played around for some time..the closest i could get to focus was seeing the laptop monitor change coulor slightly on the capture software. (and that was trying to focus on the moon!)

But removing the 1.25 adaptor and just holding the webcam in the focus tube i could instantly get focus.

I got so frustrated i tryed to make a home made adapter using an old protective cover from a set of 10x50 bins, and supprizingly it works for a big target like the moon, but not for jupiter..i just cant find it!.

Am i doing anything wrong with the barlow? i pretty much tryed everything i could think of.

[RikM]

If you take the standard 1.25" adaptor and unscrew it to expose the T-thread, then screw the top part back in from the bottom upside down you can just poke the webcam in and it should focus. At least it did with mine. I had to tape it to keep it from falling out but it didn't wobble or anything.

[spaceboy]

Sounds like a plan. Could be dubious to if the light path / collimation stays on path but at least it would get you imaging.

[Madhatter]

Fantasic idea Rik!! cant believe i didnt think of that!! i will be trying that out the moment these damn clouds finaly shift.

Just must remeber not to lose the 2 thumb screws you have to remove for it to fit:D

[RikM]

Other than crater surfing round the moon using Sharpcap as a live video viewer, I haven't tried capturing any still images like this, so I hope it works for you. For Jupiter, you have to get the camera settings and focus pretty well bang on otherwise you don't even see the planet on the screen. I found it a royal pain so am sticking with DSO imaging for the foreseeable future.

Good luck.

[Madhatter]

how do you do your DSO imaging? is your webcam modified or do you use something else? not that i could ever do it with the dob, just interested:)

[RikM]

Canon 1000D at prime focus of an Explorer 150P with a Baader MPCC mounted on an NEQ6 with a QHY5v 50mm f/4 finder-guider. I use APT for image capture, PHD for guiding, DSS for calibration and stacking and then Photoshop CS3 for post-processing.

[Madhatter]

wow that sounds like some seriouse kit!

your method works !! about 3am last night there was a gap in the clouds.. i was able to locate to moon instantly and with a bit of trial and error i also found mars!

I think the settings are completly wrong on wxastrocapture and sharpcap though , sharp cap i couldent focus, and on wxastro i could focus but things didnt look right.

Is there a way i can save a single frame from registax so i can post the pictures here?

[spaceboy]

Sounds like warm mirrors or poor seeing to me

[Spikey]

Try dropping space cowboy a PM about focusing, he uses a 250 for planetary with some amazing results.

[Madhatter]

That would be great if it was just cooling issues:) i think ym settings might be wrong but i dont have a clue where to start, i just want to get some basic footage and the have a go at some turorials about stacking. Heres what i got last night, the second pic is acctualy mars lol. Cheers for the heads up on space cowboy:) i better learn abit more first though because at the moment i am completly unsure how to do anything.

Do these pictures give any clues? its also worth saying i went for mars because jupiter was out of view by the time the clouds broke, i imagine its quite a bit of a harder target so will try for jupiter asap.

[spaceboy]

Over exposed. You need to adjust your gain, gamma, brightness in sharpcap when capturing the image.

[Stephen]

Over exposed. You need to adjust your gain, gamma, brightness in sharpcap when capturing the image.

What he said Start off by dropping the exposure well down.

[spaceboy]

This might help

[Madhatter]

Thanks guys, il go watch that tutorial now:)

[Madhatter]

ok i have watched the tutorial and have set my settings as advised.

one question though, for exsposure he sets it to 0 but i dont have that option, mine says -14 and then when dragged to the right says -4.

Do you know what settings i should use for that?

its clear here atm, scopes outside cooling off, hopefully results will be better tonight:)

[RikM]

The actual numbers I get in Sharpcap don't match any tutorials either. I just match the basic slider positions and tweak accordingly.

[Madhatter]

ok im going to go for -7 , i saw it in todd8137 video on the sidebar:)

scopes been cooling down for 2 hours, iv got it all collimated, been nice and clear..just about to go out and ...yep its covered in clouds:mad:

Im going to leave it outside and keep a good eye incase its starts to rain, just need a gap in the clouds for 10 mins! of corse more would be nice though.

[DoctorD]

Hi Madhatter

Is it just a case if not getting the target on the chip - its a bit like 6mm eyepiece - pretty narrow FOV

I would guess that even if it's a bit out of focus with a 10" scope Jupiter is going to show up pretty easily.

It's a pain trying to get Jupiter in the FOV of my little MAK and the focal length is similar to yours, infancy if I defocus it's easier as you can still see the planet if it's not centered.

Hope this helps

Paul