Eyepieces for EPP

[1CM69]

Hi all,

very green, just got my 1st scope and I need a little advice about eyepieces for eyepiece projection imaging. 

I've got a CPC925 which comes with a 40mm EP but only gives me x59 mag. 

Move ordered a couple of Celestron x-cel lx EPs a 5mm & 25mm but these will just be for viewing as they're too large in diameter to fit in my extension tube which has a max diameter of 37mm & max length of 3"

ideally I'm after similar focal length EPs but ones that'll fit my extension tube. 

 

Any help would be appreciated

thank

[1CM69]

For speed & something to play around with I've just ordered a 5mm & 25mm Ostara Plossl from Amazon very cheap

These will be with me in the morning & should fit my extension tube. 

Worth a punt

[John]

The Meade 3000 and 4000 plossls are decent quality, can be picked up used for very little and are the old standard size barrels up to the 26mm focal length. Baader Classic Orthos might be OK as well and they are really excellent quality.

[1CM69]

3 minutes ago, John said:

The Meade 3000 and 4000 plossls are decent quality, can be picked up used for very little and are the old standard size barrels up to the 26mm focal length. Baader Classic Orthos might be OK as well and they are really excellent quality.

Thanks, I'll have a look at those

[Louis D]

You might try looking for a used Scopetronix MaxView DSLR-II Eyepiece Projection Adapter.  They could hold larger diameter eyepieces.

[1CM69]

10 minutes ago, Louis D said:

You might try looking for a used Scopetronix MaxView DSLR-II Eyepiece Projection Adapter.  They could hold larger diameter eyepieces.

Thanks

[Don Pensack]

On 8/24/2016 at 10:03, 1CM69 said:

Hi all,

very green, just got my 1st scope and I need a little advice about eyepieces for eyepiece projection imaging. 

I've got a CPC925 which comes with a 40mm EP but only gives me x59 mag. 

Move ordered a couple of Celestron x-cel lx EPs a 5mm & 25mm but these will just be for viewing as they're too large in diameter to fit in my extension tube which has a max diameter of 37mm & max length of 3"

ideally I'm after similar focal length EPs but ones that'll fit my extension tube. 

 

Any help would be appreciated

thank

The CPC comes with a 40mm 1.25" eyepiece and 1.25" star diagonal.

Celestron X-Cel LX eyepieces are also 1.25", so fully compatible with your scope and its star diagonal.

It sounds like you have an extension tube from another scope, with a smaller size (0.965"??) opening.

First, you needn't use the extension tube for visual use.  Just put the eyepieces into the star diagonal.

Second, extension tubes in 1.25" are available from hundreds of retailers world-wide, so don't buy eyepieces to fit an obsolete smaller diameter, get a different extension tube.

For right now, though, you can forego the purchase of an extension tube at all since it is unnecessary for viewing.

 

[1CM69]

1 hour ago, Don Pensack said:

The CPC comes with a 40mm 1.25" eyepiece and 1.25" star diagonal.

Celestron X-Cel LX eyepieces are also 1.25", so fully compatible with your scope and its star diagonal.

It sounds like you have an extension tube from another scope, with a smaller size (0.965"??) opening.

First, you needn't use the extension tube for visual use.  Just put the eyepieces into the star diagonal.

Second, extension tubes in 1.25" are available from hundreds of retailers world-wide, so don't buy eyepieces to fit an obsolete smaller diameter, get a different extension tube.

For right now, though, you can forego the purchase of an extension tube at all since it is unnecessary for viewing.

 

it's compatible eyepieces for EPP that I am after that need to fit the tube. 

 

One of these:

https://www.amazon.co.uk/dp/B014PLRVK6/ref=pd_lpo_sbs_dp_ss_3?pf_rd_p=569136327&pf_rd_s=lpo-top-stripe&pf_rd_t=201&pf_rd_i=B00KQGV91W&pf_rd_m=A3P5ROKL5A1OLE&pf_rd_r=BGJVB9YQ73RE6ZG0R1SS

[John]

EPP = Eypiece Projection Photography ?

Presumably you are after eyepieces that are not to fat because the EPP adapter has quite a narrow aperture where the eyepiece fits ?

 

[1CM69]

15 minutes ago, John said:

EPP = Eypiece Projection Photography ?

Presumably you are after eyepieces that are not to fat because the EPP adapter has quite a narrow aperture where the eyepiece fits ?

 

Exactly, yes. I guess I wasn't clear about that in my initial post. 

Like the Meade ones you suggested yesterday. 

[Louis D]

2 hours ago, John said:

Presumably you are after eyepieces that are not to fat because the EPP adapter has quite a narrow aperture where the eyepiece fits ?

Which is why I suggested hunting down the Scopetronix adapter because it is big enough to swallow a 35mm Panoptic.

[Stu]

Which kinds of targets are you looking to image? Moon and planets?

[1CM69]

3 hours ago, Louis D said:

Which is why I suggested hunting down the Scopetronix adapter because it is big enough to swallow a 35mm Panoptic.

You did, I replied & am actively looking.

So far I have found this: http://www.adorama.com/atda.html but shipping to the UK is a crazy price, I am hunting for one in the UK.

My further replies after your suggestion are out of courtesy to the comment poster. 

[1CM69]

3 minutes ago, Stu said:

Which kinds of targets are you looking to image? Moon and planets?

Yep, Moon & Planets.

I am only going down this road of EPP after reading up on imaging & finding out that attaching a DSLR directly to a scope via a T-Adapter results in small images of targets like the Moon & planets but is a fine setup if trying to capture DSO. It was suggested that EPP be used to capture the Moon & planets to ramp up magnification.

 

Regards.., 

[Stu]

2 minutes ago, 1CM69 said:

Yep, Moon & Planets.

I am only going down this road of EPP after reading up on imaging & finding out that attaching a DSLR directly to a scope via a T-Adapter results in small images of targets like the Moon & planets but is a fine setup if trying to capture DSO. It was suggested that EPP be used to capture the Moon & planets to ramp up magnification.

 

Regards.., 

Thanks for the reply. One thing to note is that, because your scope has a long native focal length you may find it easier to use a Barlow to increase the focal length and still use prime focus photography.

Even at native focal length, you will not fit the whole lunar disk onto the sensor of a Canon 1000D for instance. For planetary work, a webcam is often easier, but still, using a x3 or x4 PowerMate would get you a reasonable image scale.

[1CM69]

Cheers for the info Stu, this is something I have read also & already have x2 Barlow with T-Adapter at the ready to try out.

My trusty DSLR is a 4/3 with a crop factor of 2, so in "effect" creates a FOV equivalent to the focal length of a lens twice that, by 35mm standards, of the lens attached to it.

In prime focus I would be getting the "same" FOV as a 35mm lens of 4700mm straight out of the box.

You know what it's like though, for each person singing the praises of the way that they do something, there's another person dissing it. I'm just trying to cover all bases after also reading that imaging through a Barlow can degrade the image.

In some instances I will be looking to create mosaics & overspill on the DSLR sensor would not matter.

Once again, thank you for your input & information, it greatly helps.

I fear this thread is slowly becoming an imaging thread, oops.

[1CM69]

I have since been using this site: https://astronomy.tools/calculators/field_of_view/

and it has helped me out vastly by letting me visualize varying combinations of eyepiece, barlow, reducers etc...

 

[Stu]

Which camera are you using?

If it helps, I can move this thread to getting started in imaging, it may get some further input there which helps you?

A poor Barlow can of course degrade and image, but a decent one should be fine. Many planetary imagers use Televue PowerMates which come in a variety of multiplying factors, up to x5 and you will not notice any degradation of image with these. The limiting factor is likely to be cooling and collimation on your scope plus the atmosphere of course, you will need good seeing.

Planetary imaging is tricky for quite a few years because the planets are pretty low even at their best during opposition.

[1CM69]

28 minutes ago, Stu said:

Which camera are you using?

If it helps, I can move this thread to getting started in imaging, it may get some further input there which helps you?

A poor Barlow can of course degrade and image, but a decent one should be fine. Many planetary imagers use Televue PowerMates which come in a variety of multiplying factors, up to x5 and you will not notice any degradation of image with these. The limiting factor is likely to be cooling and collimation on your scope plus the atmosphere of course, you will need good seeing.

Planetary imaging is tricky for quite a few years because the planets are pretty low even at their best during opposition.

My camera is an Olympus E-510, eventually I will be upgrading this to a Nikon D750 or D810 (still undecided)

perhaps moving the thread may be a good idea, thanks

[Stu]

28 minutes ago, 1CM69 said:

My camera is an Olympus E-510, eventually I will be upgrading this to a Nikon D750 or D810 (still undecided)

So, just for info these two frames are your current camera and then the full frame sensor (obviously the larger box)

[1CM69]

3 minutes ago, Stu said:

So, just for info these two frames are your current camera and then the full frame sensor (obviously the larger box)

So this is just using prime focus as is or through a Barlow?

[Stu]

Just now, 1CM69 said:

So this is just using prime focus as is or through a Barlow?

That's just at prime focus

[1CM69]

6 minutes ago, Stu said:

That's just at prime focus

No idea what I am fretting about then. 

[1CM69]

Here's an almost completely opposite question now but using an FOV calc and entering all my info for imaging plus using a 0.63 reducer, I am still looking to get very zoomed in images of for instance M42 or M31 and would need to create mosaics to capture them in their entirety.

Are there stronger reducers available? 

[John]

8 minutes ago, 1CM69 said:

Here's an almost completely opposite question now but using an FOV calc and entering all my info for imaging plus using a 0.63 reducer, I am still looking to get very zoomed in images of for instance M42 or M31 and would need to create mosaics to capture them in their entirety.

Are there stronger reducers available? 

There is a 0.33x reducer just for imaging I believe. M42 and M31 are massive targets though - I'm not sure an SCT is the tool for them in all honesty. You need a 4 degree true field to fit M31 in I think.