Pentax Q7 & Digiscoping~

bernall · 01-28-2015, 12:55 AM

Originally posted by crewl1

These are very good examples. Do you have a link to pictures of the setup and how you are adapting the scope to the camera?

Thank you crewl1

Here are some pics of the setup I am using. ED80T-CF is used as a "standard" lens with a T2 adapter.

The weight is not heavy : 3.8kg
Une petite config pour d

The adaptation is very easy and robust
Une petite config pour d

The flip-mirror can be purchased at many stores :

Renvoi coudé : Flip Mirror Vixen (renvoi coudé à miroir basculant) - Astronomie Pierro-Astro'

Vixen Optics Flip Mirror System 2680 B&H Photo Video

Vixen Photo/Visual Flip Mirror - Telescope Accessories at Telescopes

Last edited by bernall; 01-28-2015 at 10:06 AM.

reh321 · 01-28-2015, 08:44 AM

Originally posted by Kendigitize

Here's my pentax Q with the 01 prime lens, digiscoping adapter and Orion Skyscanner 100 reflector. Did a few test shoots of the moon and am happy with my first try. There's some heavy CA around the bright edge of the moon, but I'm not using a moon filter or anything and I think that will help.

Exactly what is a moon filter? If I use a regular, but very long, K-mount lens to photograph the moon, what would be a good choice for me to use in the stead of a moon filter?

**crewl1** · 01-28-2015, 09:55 AM

Originally posted by bernall

Thank you crewl1

Here are some pics of the setup I am using. ED80T-CF is used as a "standard" lens with a T2 adapter.

The weight is not heavy : 3.8kg
Une petite config pour d

The adaptation is very easy and robust
Une petite config pour d

The flip-mirror can be purchased at many stores :

Renvoi coudé : Flip Mirror Vixen (renvoi coudé à miroir basculant) - Astronomie Pierro-Astro'

Vixen Optics Flip Mirror System 2680 B&H Photo Video

Vixen Photo/Visual Flip Mirror - Telescope Accessories at Telescopes

Thanks for the info. The images are very sharp.
A few other questions:
What is the resulting focal length with the crop factor on the Q7?
What is the aperture you are shooting at?

bernall · 01-28-2015, 10:04 AM

Originally posted by Kendigitize

There's some heavy CA around the bright edge of the moon, but I'm not using a moon filter or anything and I think that will help.

CA are due to the "afocal setup".

"Minus violet" or "fringe killer" filter may attenuate the CA, but it's not satisfaying IMO, and it's expensive.

The setup without ocular and without prime lense (the scope as a lens with t2 adapter) is much better.

---------- Post added 01-28-15 at 06:18 PM ----------

Originally posted by crewl1

Thanks for the info. The images are very sharp.
A few other questions:
What is the resulting focal length with the crop factor on the Q7?
What is the aperture you are shooting at?

Yes, very very sharp. IMO, there is the same difference between bigma and DA300mm and between DA300mm and ED80T-CF

I tried to explane that with the number of lens in a bigma or in afocal-setup (about 20 lens or more) and only three with a triplet apo-chromatic as in ED80T-CF.

I compared hand held 100-300mm panasonic zoom VR on (crop 100%)

and ed80t-cf on tripod (crop 100%)

http://www.chassimages.com/forum/index.php/topic,217130.0/all.html

The focal lenght of the ED80T-CF is 480mm.

the equivalent (not resulting) FF focal lengh is around 2200mm on Q7, 2700mm on Q, and only 960mm on µ4/3.

The aperture is constant : 6, enough in most cases, due to a better transmission (only 3 lenses inside).

Last edited by bernall; 01-28-2015 at 10:39 AM.

Kendigitize · 01-28-2015, 12:37 PM

Originally posted by reh321

Exactly what is a moon filter? If I use a regular, but very long, K-mount lens to photograph the moon, what would be a good choice for me to use in the stead of a moon filter?

The moon filter is for telescope eyepieces. It's just a polarized filter to cut the brightness so you can get more detail when the moon is in full phase. For a regular DSLR lens I always start with F8, iso100, 1/120 and go from there.

---------- Post added 01-28-15 at 11:48 AM ----------

Originally posted by bernall

Thank you crewl1

Here are some pics of the setup I am using. ED80T-CF is used as a "standard" lens with a T2 adapter.

I don't know if you posted a link for the ED80T-CF yet. Here it is at Orion telescopes with all the specs and info. I think they make a non-carbon fiber version of this scope too, with less coatings for about about 1/2 the price :
ED80T CF Triplet Apochromatic Refractor Telescope | Orion Telescopes

**crewl1** · 01-28-2015, 12:49 PM

Originally posted by bernall

CA are due to the "afocal setup".

"Minus violet" or "fringe killer" filter may attenuate the CA, but it's not satisfaying IMO, and it's expensive.

The setup without ocular and without prime lense (the scope as a lens with t2 adapter) is much better.

---------- Post added 01-28-15 at 06:18 PM ----------

Yes, very very sharp. IMO, there is the same difference between bigma and DA300mm and between DA300mm and ED80T-CF

I tried to explane that with the number of lens in a bigma or in afocal-setup (about 20 lens or more) and only three with a triplet apo-chromatic as in ED80T-CF.

I compared hand held 100-300mm panasonic zoom VR on (crop 100%)

and ed80t-cf on tripod (crop 100%)

http://www.chassimages.com/forum/index.php/topic,217130.0/all.html

The focal lenght of the ED80T-CF is 480mm.

the equivalent (not resulting) FF focal lengh is around 2200mm on Q7, 2700mm on Q, and only 960mm on µ4/3.

The aperture is constant : 6, enough in most cases, due to a better transmission (only 3 lenses inside).

Thanks for this information. I am very intrigued and will start to assemble the pieces once finances allow.
I thought the DA*300 was the ultimate lens for the Q, but this is much better.

Are there any disadvantages or problems to be aware of?

I will have to run a translator on the other forum, as I am sure you have already covered all of this there, sorry.

bernall · 01-29-2015, 11:25 AM

Originally posted by crewl1

Thanks for this information. I am very intrigued and will start to assemble the pieces once finances allow.

Sell it

Quote:

I thought the DA*300 was the ultimate lens for the Q, but this is much better.

I am very intrigued too

. My opinion was different but now ...

Quote:

Are there any disadvantages or problems to be aware of?

Because of the electronic shutter, it's very hard to shoot without a remote IR, a good tripod, no wind, and so on... : no birds fly, without mega-luck. Perhaps the Pentax Q-K adapter may improve the setup, but it is more expensive than Q/Q7...

Quote:

I will have to run a translator on the other forum, as I am sure you have already covered all of this there, sorry.

Sorry

thank you for the interest.

I can continue to answer any question ... in my english... with my english ... something like that

A restless bird at 12m (2200mm eq focal lenght)

SteveNunez · 01-29-2015, 11:42 AM

Amazing sharpness- but wouldn't this be a 480mm lens "all the time" with no option to zoom out?
Seems very limiting in that it would only be suitable for very long range photography..............amazing sharpness however.

Where can I get more info on lenses like this?

Kendigitize · 01-29-2015, 12:03 PM

Originally posted by SteveNunez

Amazing sharpness- but wouldn't this be a 480mm lens "all the time" with no option to zoom out?
Seems very limiting in that it would only be suitable for very long range photography..............amazing sharpness however.

Where can I get more info on lenses like this?

Yes, it's a 480mm telescope when not using an eyepiece. It's excellent for birds, boats, etc., but where it really shines is astrophotography and deep sky images.
Here's a link to the same TELESCOPE at Orion Telescopes as well as other similar models, mounts, etc.

ED80T CF Triplet Apochromatic Refractor Telescope | Orion Telescopes.

Phenix jc · 01-29-2015, 12:12 PM

Originally posted by SteveNunez

Amazing sharpness- but wouldn't this be a 480mm lens "all the time" with no option to zoom out?
Seems very limiting in that it would only be suitable for very long range photography..............amazing sharpness however.

Where can I get more info on lenses like this?

Hi Steve,
(Congrats with your Osprey sessions!)
I've opened a separate thread now, but I only second Bernall in that

**crewl1** · 01-29-2015, 12:27 PM

@bernall
You said : Because of the electronic shutter, it's very hard to shoot without a remote IR, a good tripod, no wind, and so on... : no birds fly, without mega-luck. Perhaps the Pentax Q-K adapter may improve the setup, but it is more expensive than Q/Q7...

I have used simple adapters in the past but now use the Pentax K-Q adapter.
How could that be used here being that the adapter used is a T2-Q, without a K mount option?

Kendigitize · 01-29-2015, 12:42 PM

Originally posted by crewl1

@bernall
You said : Because of the electronic shutter, it's very hard to shoot without a remote IR, a good tripod, no wind, and so on... : no birds fly, without mega-luck. Perhaps the Pentax Q-K adapter may improve the setup, but it is more expensive than Q/Q7...

I have used simple adapters in the past but now use the Pentax K-Q adapter.
How could that be used here being that the adapter used is a T2-Q, without a K mount option?

Pentax Q-K adapter with Kmount T2 adapter ring? Would that still allow exp. up to 30sec with the Q?

bernall · 01-29-2015, 12:53 PM

Hi Ken and Crewl1,

Bonsoir Phenix JC,

Originally posted by Kendigitize

Pentax Q-K adapter with Kmount T2 adapter ring? Would that still allow exp. up to 30sec with the Q?

Yes, exactly : you need a K-T2 adapter ring in addition with the Pentax Q-K adapter.

I don't have the Pentax Q-K adapter, so I'm not sure, but I suppose it allows exposure up to 30sec, as a K mount lens.

---------- Post added 01-29-15 at 09:07 PM ----------

Originally posted by SteveNunez

Amazing sharpness- but wouldn't this be a 480mm lens "all the time" with no option to zoom out?
Seems very limiting in that it would only be suitable for very long range photography..............amazing sharpness however.

Where can I get more info on lenses like this?

Hello Steve

Ken gived the answer: yes, it is a fix-focal lenght lense, no zoom at all.

The only advantage is a fantastic sharpness , near the theoretical possibilities of a 80mm diameter lens.

Many clones are avalaible around the world, for example :

in France : Lunette 80\/80
in Gremany : Teleskop-Express: TS Super Apo 80/480mm F/6 - Triplet FPL-53 - colour free

but only Orion delivers (via re-dealers in different states) the (not essential) carbon fiber model.

Be carefull, some clones are made of glass of second rank quality or are doublet (only two lenses), not triplet (three lenses). Only FPL-53 glass produces such CA-free pictures, IMO, combined with an aperture f/6. In astrophotography, it's not very distinguishable, but for wildlife photography, it's clearly a big difference. I had an Equinox ED80 before (FPL53 doublet), the color fringes were sometimes much more visible.

Kendigitize · 01-29-2015, 01:13 PM

Originally posted by bernall

Hi Ken and Crewl1,

Bonsoir Phenix JC,

Yes, exactly : you need a K-T2 adapter ring in addition with the Pentax Q-K adapter.

I don't have the Pentax Q-K adapter, so I'm not sure, but I suppose it allows exposure up to 30sec, as a K mount lens.

The Pentax Q adapter is 5.5X magnification. Wouldn't that make it 12,375mm ? Also the built-in mechanical shutter helps to prevent rolling shutter distortion when working with moving subjects.

bernall · 01-29-2015, 01:19 PM

Originally posted by Kendigitize

The Pentax Q adapter is 5.5X magnification. Wouldn't that make it 12,375mm ? Also the built-in mechanical shutter helps to prevent rolling shutter distortion when working with moving subjects.

The crop factor of the Q sensor is 5,5x : it does not depend on the adapter ring. So the focal length is equivalent to 5.5x480mm= 2640mm (with a FF sensor).

The big advantage of the PentaxQ-K adaptor is the built-in mechanical shutter, as you say, to prevent rolling shutter in case of wind for example.

01-28-2015, 12:37 PM	#20
Kendigitize Veteran Member Join Date: Apr 2013 Photos: Gallery Posts: 324	Originally posted by reh321 Exactly what is a moon filter? If I use a regular, but very long, K-mount lens to photograph the moon, what would be a good choice for me to use in the stead of a moon filter? The moon filter is for telescope eyepieces. It's just a polarized filter to cut the brightness so you can get more detail when the moon is in full phase. For a regular DSLR lens I always start with F8, iso100, 1/120 and go from there. ---------- Post added 01-28-15 at 11:48 AM ---------- Originally posted by bernall Thank you crewl1 Here are some pics of the setup I am using. ED80T-CF is used as a "standard" lens with a T2 adapter. I don't know if you posted a link for the ED80T-CF yet. Here it is at Orion telescopes with all the specs and info. I think they make a non-carbon fiber version of this scope too, with less coatings for about about 1/2 the price : ED80T CF Triplet Apochromatic Refractor Telescope \| Orion Telescopes Last edited by Kendigitize; 01-28-2015 at 03:48 PM.

01-29-2015, 12:53 PM	#28
bernall Junior Member Join Date: Oct 2013 Location: Lyon Posts: 30	Hi Ken and Crewl1, Bonsoir Phenix JC, Originally posted by Kendigitize Pentax Q-K adapter with Kmount T2 adapter ring? Would that still allow exp. up to 30sec with the Q? Yes, exactly : you need a K-T2 adapter ring in addition with the Pentax Q-K adapter. I don't have the Pentax Q-K adapter, so I'm not sure, but I suppose it allows exposure up to 30sec, as a K mount lens. ---------- Post added 01-29-15 at 09:07 PM ---------- Originally posted by SteveNunez Amazing sharpness- but wouldn't this be a 480mm lens "all the time" with no option to zoom out? Seems very limiting in that it would only be suitable for very long range photography..............amazing sharpness however. Where can I get more info on lenses like this? Hello Steve Ken gived the answer: yes, it is a fix-focal lenght lense, no zoom at all. The only advantage is a fantastic sharpness , near the theoretical possibilities of a 80mm diameter lens. Many clones are avalaible around the world, for example : in France : Lunette 80\/80 in Gremany : Teleskop-Express: TS Super Apo 80/480mm F/6 - Triplet FPL-53 - colour free but only Orion delivers (via re-dealers in different states) the (not essential) carbon fiber model. Be carefull, some clones are made of glass of second rank quality or are doublet (only two lenses), not triplet (three lenses). Only FPL-53 glass produces such CA-free pictures, IMO, combined with an aperture f/6. In astrophotography, it's not very distinguishable, but for wildlife photography, it's clearly a big difference. I had an Equinox ED80 before (FPL53 doublet), the color fringes were sometimes much more visible. Last edited by bernall; 01-29-2015 at 01:40 PM.

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01-28-2015, 12:55 AM	#16
bernall Junior Member Join Date: Oct 2013 Location: Lyon Posts: 30	Originally posted by crewl1 These are very good examples. Do you have a link to pictures of the setup and how you are adapting the scope to the camera? Thank you crewl1 Here are some pics of the setup I am using. ED80T-CF is used as a "standard" lens with a T2 adapter. The weight is not heavy : 3.8kg Une petite config pour d The adaptation is very easy and robust Une petite config pour d The flip-mirror can be purchased at many stores : Renvoi coudé : Flip Mirror Vixen (renvoi coudé à miroir basculant) - Astronomie Pierro-Astro' Vixen Optics Flip Mirror System 2680 B&H Photo Video Vixen Photo/Visual Flip Mirror - Telescope Accessories at Telescopes Last edited by bernall; 01-28-2015 at 10:06 AM.

01-28-2015, 08:44 AM	#17
reh321 Pentaxian Join Date: Nov 2014 Location: South Bend, IN, USA Photos: Gallery \| Albums Posts: 23,180	Originally posted by Kendigitize Here's my pentax Q with the 01 prime lens, digiscoping adapter and Orion Skyscanner 100 reflector. Did a few test shoots of the moon and am happy with my first try. There's some heavy CA around the bright edge of the moon, but I'm not using a moon filter or anything and I think that will help. Exactly what is a moon filter? If I use a regular, but very long, K-mount lens to photograph the moon, what would be a good choice for me to use in the stead of a moon filter?

01-28-2015, 09:55 AM	#18
crewl1 Site Supporter Join Date: Jul 2010 Location: Los Angeles, CA Photos: Gallery \| Albums Posts: 9,807	Originally posted by bernall Thank you crewl1 Here are some pics of the setup I am using. ED80T-CF is used as a "standard" lens with a T2 adapter. The weight is not heavy : 3.8kg Une petite config pour d The adaptation is very easy and robust Une petite config pour d The flip-mirror can be purchased at many stores : Renvoi coudé : Flip Mirror Vixen (renvoi coudé à miroir basculant) - Astronomie Pierro-Astro' Vixen Optics Flip Mirror System 2680 B&H Photo Video Vixen Photo/Visual Flip Mirror - Telescope Accessories at Telescopes Thanks for the info. The images are very sharp. A few other questions: What is the resulting focal length with the crop factor on the Q7? What is the aperture you are shooting at?

01-28-2015, 10:04 AM	#19
bernall Junior Member Join Date: Oct 2013 Location: Lyon Posts: 30	Originally posted by Kendigitize There's some heavy CA around the bright edge of the moon, but I'm not using a moon filter or anything and I think that will help. CA are due to the "afocal setup". "Minus violet" or "fringe killer" filter may attenuate the CA, but it's not satisfaying IMO, and it's expensive. The setup without ocular and without prime lense (the scope as a lens with t2 adapter) is much better. ---------- Post added 01-28-15 at 06:18 PM ---------- Originally posted by crewl1 Thanks for the info. The images are very sharp. A few other questions: What is the resulting focal length with the crop factor on the Q7? What is the aperture you are shooting at? Yes, very very sharp. IMO, there is the same difference between bigma and DA300mm and between DA300mm and ED80T-CF I tried to explane that with the number of lens in a bigma or in afocal-setup (about 20 lens or more) and only three with a triplet apo-chromatic as in ED80T-CF. I compared hand held 100-300mm panasonic zoom VR on (crop 100%) and ed80t-cf on tripod (crop 100%) http://www.chassimages.com/forum/index.php/topic,217130.0/all.html The focal lenght of the ED80T-CF is 480mm. the equivalent (not resulting) FF focal lengh is around 2200mm on Q7, 2700mm on Q, and only 960mm on µ4/3. The aperture is constant : 6, enough in most cases, due to a better transmission (only 3 lenses inside). Last edited by bernall; 01-28-2015 at 10:39 AM.

01-28-2015, 12:49 PM	#21
crewl1 Site Supporter Join Date: Jul 2010 Location: Los Angeles, CA Photos: Gallery \| Albums Posts: 9,807	Originally posted by bernall CA are due to the "afocal setup". "Minus violet" or "fringe killer" filter may attenuate the CA, but it's not satisfaying IMO, and it's expensive. The setup without ocular and without prime lense (the scope as a lens with t2 adapter) is much better. ---------- Post added 01-28-15 at 06:18 PM ---------- Yes, very very sharp. IMO, there is the same difference between bigma and DA300mm and between DA300mm and ED80T-CF I tried to explane that with the number of lens in a bigma or in afocal-setup (about 20 lens or more) and only three with a triplet apo-chromatic as in ED80T-CF. I compared hand held 100-300mm panasonic zoom VR on (crop 100%) and ed80t-cf on tripod (crop 100%) http://www.chassimages.com/forum/index.php/topic,217130.0/all.html The focal lenght of the ED80T-CF is 480mm. the equivalent (not resulting) FF focal lengh is around 2200mm on Q7, 2700mm on Q, and only 960mm on µ4/3. The aperture is constant : 6, enough in most cases, due to a better transmission (only 3 lenses inside). Thanks for this information. I am very intrigued and will start to assemble the pieces once finances allow. I thought the DA*300 was the ultimate lens for the Q, but this is much better. Are there any disadvantages or problems to be aware of? I will have to run a translator on the other forum, as I am sure you have already covered all of this there, sorry.

01-29-2015, 11:25 AM	#22
bernall Junior Member Join Date: Oct 2013 Location: Lyon Posts: 30	Originally posted by crewl1 Thanks for this information. I am very intrigued and will start to assemble the pieces once finances allow. Sell it Quote: I thought the DA*300 was the ultimate lens for the Q, but this is much better. I am very intrigued too . My opinion was different but now ... Quote: Are there any disadvantages or problems to be aware of? Because of the electronic shutter, it's very hard to shoot without a remote IR, a good tripod, no wind, and so on... : no birds fly, without mega-luck. Perhaps the Pentax Q-K adapter may improve the setup, but it is more expensive than Q/Q7... Quote: I will have to run a translator on the other forum, as I am sure you have already covered all of this there, sorry. Sorry thank you for the interest. I can continue to answer any question ... in my english... with my english ... something like that A restless bird at 12m (2200mm eq focal lenght)

01-29-2015, 11:42 AM	#23
SteveNunez Senior Member Join Date: Feb 2008 Location: Fort Lauderdale, Florida Photos: Gallery Posts: 230 Original Poster	Amazing sharpness- but wouldn't this be a 480mm lens "all the time" with no option to zoom out? Seems very limiting in that it would only be suitable for very long range photography..............amazing sharpness however. Where can I get more info on lenses like this?

01-29-2015, 12:03 PM	#24
Kendigitize Veteran Member Join Date: Apr 2013 Photos: Gallery Posts: 324	Originally posted by SteveNunez Amazing sharpness- but wouldn't this be a 480mm lens "all the time" with no option to zoom out? Seems very limiting in that it would only be suitable for very long range photography..............amazing sharpness however. Where can I get more info on lenses like this? Yes, it's a 480mm telescope when not using an eyepiece. It's excellent for birds, boats, etc., but where it really shines is astrophotography and deep sky images. Here's a link to the same TELESCOPE at Orion Telescopes as well as other similar models, mounts, etc. ED80T CF Triplet Apochromatic Refractor Telescope \| Orion Telescopes.

01-29-2015, 12:12 PM	#25
Phenix jc Senior Member Join Date: Jan 2015 Posts: 105	Originally posted by SteveNunez Amazing sharpness- but wouldn't this be a 480mm lens "all the time" with no option to zoom out? Seems very limiting in that it would only be suitable for very long range photography..............amazing sharpness however. Where can I get more info on lenses like this? Hi Steve, (Congrats with your Osprey sessions!) I've opened a separate thread now, but I only second Bernall in that

01-29-2015, 12:27 PM	#26
crewl1 Site Supporter Join Date: Jul 2010 Location: Los Angeles, CA Photos: Gallery \| Albums Posts: 9,807	@bernall You said : Because of the electronic shutter, it's very hard to shoot without a remote IR, a good tripod, no wind, and so on... : no birds fly, without mega-luck. Perhaps the Pentax Q-K adapter may improve the setup, but it is more expensive than Q/Q7... I have used simple adapters in the past but now use the Pentax K-Q adapter. How could that be used here being that the adapter used is a T2-Q, without a K mount option?

01-29-2015, 12:42 PM	#27
Kendigitize Veteran Member Join Date: Apr 2013 Photos: Gallery Posts: 324	Originally posted by crewl1 @bernall You said : Because of the electronic shutter, it's very hard to shoot without a remote IR, a good tripod, no wind, and so on... : no birds fly, without mega-luck. Perhaps the Pentax Q-K adapter may improve the setup, but it is more expensive than Q/Q7... I have used simple adapters in the past but now use the Pentax K-Q adapter. How could that be used here being that the adapter used is a T2-Q, without a K mount option? Pentax Q-K adapter with Kmount T2 adapter ring? Would that still allow exp. up to 30sec with the Q?

01-29-2015, 01:13 PM	#29
Kendigitize Veteran Member Join Date: Apr 2013 Photos: Gallery Posts: 324	Originally posted by bernall Hi Ken and Crewl1, Bonsoir Phenix JC, Yes, exactly : you need a K-T2 adapter ring in addition with the Pentax Q-K adapter. I don't have the Pentax Q-K adapter, so I'm not sure, but I suppose it allows exposure up to 30sec, as a K mount lens. The Pentax Q adapter is 5.5X magnification. Wouldn't that make it 12,375mm ? Also the built-in mechanical shutter helps to prevent rolling shutter distortion when working with moving subjects.

01-29-2015, 01:19 PM	#30
bernall Junior Member Join Date: Oct 2013 Location: Lyon Posts: 30	Originally posted by Kendigitize The Pentax Q adapter is 5.5X magnification. Wouldn't that make it 12,375mm ? Also the built-in mechanical shutter helps to prevent rolling shutter distortion when working with moving subjects. The crop factor of the Q sensor is 5,5x : it does not depend on the adapter ring. So the focal length is equivalent to 5.5x480mm= 2640mm (with a FF sensor). The big advantage of the PentaxQ-K adaptor is the built-in mechanical shutter, as you say, to prevent rolling shutter in case of wind for example.