Newbie question/s

[Dazzyd]

Hi all

I'd like to do some imaging for the Venus transit but looking into that and some of the amazing images posted on here I'd like to do some solar imaging irrespective of Venus. I've got a 150PL with a Nikon D80 and a t-ring (not used it yet). I'm going to get a solar filter ordered probably tonight from FLO (so I'll probably have it on Saturday so I can start practising ) but to get the surface texture detail, do I need any other filters? Or will good exposure setting and focus do the job with some processing in Photoshop later?

Thanks for any help you can give guys

[Steve Ward]

I tend to shoot a run of about 50 frames in RAW mode and then stack them in Registax5.

Have no set procedure for the wavelet tweaks , just have a play and see how you get on.

Haven't got into the Photoshop area yet but as long as you save as you go thru the procedure you can always have another play at a later date.

Check out Youtube for Registax tutorials to get you started .

Have fun ....

[Steve Ward]

P.S. Focus is the key to start with.

[Dazzyd]

Thanks Steve. Having just the D80 body connected to the scope (120mm focal length), what sort of size would I expect to see on the images? Would I see the whole disc or partial? I've wanted to try the D80 and t-ring out on the moon but I aint staying up till 3 in the morning for that, I'll wait till the moon comes around at a more civil time LOL. So, I have no idea what sort of views I should expect from it.

Thanks again

[GreatAttractor]

Image size at prime focus can be easily calculated ("ang_d" is the object's angular diameter in radians):

0.5 * img_size / f = tan(0.5 * ang_d)

For common targets the angular diameter is small, so we can approximate tan(x) ≈ x, which simplifies the formula to:

img_size = ang_d * f

To get size in pixels just divide img_size by D80's pixel size. Moon's angular diameter is about 0.5 deg = 0.5*pi/180 rad.

[Steve Ward]

Punched your details into Stellarium Ocular plug-in , gave me this.

(Canon sensor about same size as D80)

[jgs001]

That Stellarium image is just about right. I use 1200mm for both the moon and sun (with appropriate filters) and my Canon SLR and it's a nice fit, the disk sits nicely with some space around it, and you don't need to crop.

About like this, scaled for the web. This is white light, with a custom colour applied in processing.

[Dazzyd]

Thanks guys. I must get the ocular plugin for Stellarium! I need to wait a while for the moon to come round but I've just ordered some Baader Solar Film so I should be able to get some sun shots very soon

[Stephen]

Thanks guys. I must get the ocular plugin for Stellarium! I need to wait a while for the moon to come round but I've just ordered some Baader Solar Film so I should be able to get some sun shots very soon

It comes with it by default If for some reason you don't have it, you must have a very old version?

[Dazzyd]

Or maybe I just don't know what I'm fully doing with it yet LOL Think I need to read or watch some tutorials LOL

[Steve Ward]

Try this.

[Dazzyd]

Thanks Steve that's helped a huge amount! Put my D80 details in and the Sun should fill almost all of the height of the shot with some spare room for flares etc. Rather excited now! Just starting to make my solar filter, can't believe I haven't got a compass to draw the circle! Trip down the all night Tesco I think I'd like to have it all ready for when the Solar Film arrives.

Oooo I love it when I get excited about stuff, I ought to know better now at 40 years old but I'm such a kid LOL

[Steve Ward]

Can you not find an appropriately sized object to draw round , saucer maybe ?

[Steve Ward]

Save you (i) a trip to Tesco

(ii) putting a hole in the film with the compass point !!!!!!!!!!

[Dazzyd]

Film hasn't arrived yet, hopefully tomorrow. None of my chinaware were the right size LOL. Tesco was only 5 mins away