Too Bright

[scarecrow]

I was viewing Jupiter last night and it was a little too bright to pick out any detail. Is there a filter i can get that dims it a bit. The scope im using is a 200p skywatcher.

Also i tried for the first time to hook my dslr nikon D40 up to it.

I think i have the setup all wrong as i connected the camera to the barlow lens and then into the scope. The camera kept telling me no lens was connected so not sure what i was doing wrong.

Any help would be good.

One more question, What size eyepiece do you use to see jupiter.

I was using a 12.5mm but it was a little small. I do have a 7.5mm but it was a bit blury. The eyepieces i have with the scope are 7.5mm, 12.5mm, 25mm and a 40mm.

Thanks for the help

[Digz]

There a various filters around that can help pick out detail in objects. Unfortunately thats as far as my knowledge goes.

As for the D40 issue this is to be expected as there is no lens connected! When doing AP with a DSLR you will want to be shooting in Manual mode so you can set the bulb exposure. The issue of no lens shouldnt prevent this from happening, all you should get is an error reading for the aperture.

Hopefully someone soon will chip in with a answer to your other questions

[scarecrow]

Is that the right way to connect the camera to the telescope tho?

[jgs001]

it's certainly a way to connect the camera to the scope, and that's sort of how I do single shots of the moon and sun (with the correct filter), although I use a photo teleconverter instead of a barlow. Jupiter, however, being much smaller is going to need a lot more magnification with an SLR than the moon. I tried planetary with my SLR a while back, and needed 20x worth of barlow to get any kind of image scale (although I was going for Venus). As has been said, set the camera to manual mode, the lack of electrical contacts shouldn't be a problem.

As for the ep, if the 7.5 is tricky, then use the 12.5 and the 2x barlow.

[Digz]

Well it all depends.

Presumably you have a T ring which connects to your camera (in place of a lens) and then a T adapter which allows all of this to connect to your scope? If so then this is correct for Prime Focus AP i.e. you are effectively using the scope as a large lens. You can use a Barlow in the mix and may find this is need to achieve enough inward travel for focus (unless you have fathomed out how to dismantle the 1.25" adapter for your scope, assuming its similar to my SW 250p ds?)

HTH

[Digz]

Damn you John, ya beat me to it, lol

[barkis]

Barlow Projection is a good way to double the native focal length of your telescope. Assuming you are using a x2 Barlow.

Use a low power eyepiece to centre the planet, then take the EP out, put in the Barlow when it has been attached to the camera.

So, what you have, is Barlow in the focuser, camera attached to Barlow, camera on Manual ISO 200 - 400, carefully focus on the planet. Small focus movements at a time.

If you are using a Newtonian, there is a possibility you won't have enough in focus to allow the image to focus on the cameras sensor.

Try the camera in the focuser on its own, and see if you can get a good focus on the moon, or Jupiter . You should see the planet in sharp focus, and possibly some of Jupiters moons beside the planet.

Ron.

[RayGil]

Hello.

If the image is to bright in the eyepiece, which is normally the case at lower mag (20mm +) try using your high power eyepiece, say a 5mm that will actually dim the image slightly and may allow you to pick up some detail, failing that then it sounds like you need a eyepiece filter, but you should be able to pick out detail without one.

On the Camera, I have a Canon, It has to be set to manual, bulb setting, otherwise it thinks that there should be a lens on the front, and won't do anything.

Just putting a barlow on the front is not enough really, Can I point you to my blog, it may give you some direction and more info, I am currently in the process of setting up astrophotography using very basic equipment.

My External Blog : Ray's Astro-Photography Site

Ray

[Steve1976]

Scarecrow about using a filter - I've sometimes found that my lunar filter can be quite helpful in getting a little more detail out of jupiter when it is too bright. I've tried some coloured filters but to be honest I don't personally find them very useful. I also find that the 7.5 mm makes the image too blurry. I tend to use my 10mm and also a 17.5 mm the latter actually giving the better views. Maybe its just a better quality EP than the 10mm which came with the scope.

[scarecrow]

Thanks for the info.

With the 12.5mm lens jupiter is about 8mm across.

Is that about right?

[GME]

Hi

Just a note, the reason for the 7,5 mm EP showing you a blurred view may be the fact that your current seeing conditions aren't good enough allowing you to use that high magnification. This is due to turbulence in the air layers, caused by heat etc.

You may want to try using as suggested above a 12,5 mm EP in combination with a 2x Barlow (equivalent to a 6,25 mm EP) if you get a nice view then, well you're 7,5 mm EP belongs in in the dustbin or the like, if you get a similar blurry image keep you 7,5 mm EP and try it another day or later at night, the seeing conditions do change

[John]

I found the viewing conditions last night (I'm in the West Country) prohibited high power use on Jupiter. I used 118x with my 4" refractor for the best views. Jupiter, unlike Saturn, does not seem to soak up high magnification well.

You should have been ok with a 7mm in your 200mm scope through, despite the conditions - had the scope cooled down properly and is it in decent collimation ?.

[jgs001]

Just want to add about the comments the camera has to be manual bulb mode, that's not really the case. In fact bulb mode is going to give you problems for the moon and planets as it will over expose. I regularly use Av mode for flats with my 450d attached to the scope and never a complaint. I did have to tape my teleconverter contacts to stop the camera having a fit about not having a lens attached mind you.

[Digz]

Just want to add about the comments the camera has to be manual bulb mode, that's not really the case. In fact bulb mode is going to give you problems for the moon and planets as it will over expose. I regularly use Av mode for flats with my 450d attached to the scope and never a complaint. I did have to tape my teleconverter contacts to stop the camera having a fit about not having a lens attached mind you.

Yeah, fair comment. I was assuming long exposures for DSOs etc but your quite right. Having said that there is still no reason while manual mode cannot be used and the correct shutter speed selected i.e. 1/250th or thereabouts for the moon etc. I must admit I haven't tried shooting with my D200 attached in anything other than manual, I assume you could shoot in shutter priority and it would still work.