Building a VERY basic wedge....but:

[Alan_W1]

Hello all,

I need some confirmation regarding my Latitude setting on my ioptron base.

After capturing encouraging first results of the moon, using my longest/heaviest telephoto gear, plonked on top of a video head and tripod, i have decided to build a wedge for it, to slightly increase the versatility of that set-up, for static lunar use {and hopefully Jupiter etc} in my little west-facing backyard {not for mobile situations}....therefore i probably only require a basic polar alignment, as i am not using motors to guide, but do need to manually tweak the image occasionally, to keep it more in position within the frame...as it moves across {to avoid major cropping when shooting for stacking purposes}.

I had thought of getting a second-hand EQ mount off Ebay for my largest set-up, but i don't want to spend too much cash for a limited use....especially as i would be over the payload limit for an EQ3-2....and a more suitable EQ5 would not be worthwhile for my limited situations {i have too much gear as it is}.

My Ioptron Skyguider Pro is ideal for my mobile/lightweight set-up, of short/medium lens gear, but not suitable for the big stuff....therefore a wedge option with my video head seems worth a shot.

I have yet to use the Ioptron yet {lack of clear enough skies to view Polaris, since owning it}, so have set my latitude on the grid at my 54.3' degrees location {marked with the red arrow}, but i am unsure if that is correct, as i would have expected the top of the grid to have 90 degrees instead of 0 degrees. Therefore i can't get my head around whether i have set it correctly, or it should be set at 35.7' degrees {from the top} on this specific grid.



I have cobbled together this wedge, which i have lined-up with the elevation of the ioptron base latitude setting, but have not fully locked it down permanently/securely yet {for a general polar alignment}...until i can confirm my latitude has been set correctly on the ioptron.

Any help or confirmation is appreciated. I'm sure it is a simple answer, but my old brain is getting older by the second.

cheers.

 

[W5JCK]

You do have it set correctly. You can confirm by making sure it points at the proper elevation for Polaris. The tripod will have to be level of course.

I will say that your tripods look a bit flimsy for tracking with large telephoto lenses or telescopes. I would get a sturdier one, or at least hang some weight beneath the tripod. Regardless of whether or not you track, the tripod will need to be sturdy because vibrations and movements can easily ruin images.

 

[Alan_W1]

You do have it set correctly. You can confirm by making sure it points at the proper elevation for Polaris. The tripod will have to be level of course.

I will say that your tripods look a bit flimsy for tracking with large telephoto lenses or telescopes. I would get a sturdier one, or at least hang some weight beneath the tripod. Regardless of whether or not you track, the tripod will need to be sturdy because vibrations and movements can easily ruin images.

Thanks for putting my mind at rest. I shall be tweaking it to make it more exact when/if the skies clear enough for a glimpse at Polaris.

I think i may have overdosed on youtube videos for confirmation of my dial setting, as i initially thought it was right...but some videos had put doubt in my mind, and i had started to convince myself otherwise.

Phew!!!!

Thanks again.

 

[Alan_W1]

You do have it set correctly. You can confirm by making sure it points at the proper elevation for Polaris. The tripod will have to be level of course.

I will say that your tripods look a bit flimsy for tracking with large telephoto lenses or telescopes. I would get a sturdier one, or at least hang some weight beneath the tripod. Regardless of whether or not you track, the tripod will need to be sturdy because vibrations and movements can easily ruin images.

Thanks for putting my mind at rest. I shall be tweaking it to make it more exact when/if the skies clear enough for a glimpse at Polaris.

I think i may have overdosed on youtube videos for confirmation of my dial setting, as i initially thought it was right...but some videos had put doubt in my mind, and i had started to convince myself otherwise.

Phew!!!!

Thanks again.

Just to add:

Yes, you may be right regarding the tripods....for Astro stuff.

They are perfectly fine for my usual use with the intended camera/lens combinations {wildlife video}, as they are rarely fully extended....although i agree the effective FL's i will likely use for lunar stuff will likely push them to their limits....although the shutter speeds i will need should be quicker than used with my wildlife video, so hopefully that will help me out if needed.

I also have a sturdier/relatively heavier {video specific} tripod {which i leave on site for certain wildlife scenarios} that i can try for astro purposes, although it only extends to the middle of my thigh...so maybe too short to 'see' over the wall of my backyard {but i shall have a think about that, if needs be}.

I have experimented on distant terrestial subjects for wobble, at the longest effective fl's i'm likely to use for lunar stuff, and the video head stabilises any small wobbles far quicker than a large locked down ballhead {for example} due to its in-built drag, and the wedge is capable of locking in place far more securely than the ioptron wedge

The set-up is also more stable than my first efforts of the moon with this camera/lens, as i couldn't balance the entire set-up over the three legs of the tripod when pointing the lens at a very steep upwards angle {it was all hanging over one leg}, whereas the wedge allows me to balance the entire payload over all of the tripod legs.

That said, i shall give it a try in my backyard {where i can probably create a wind screen if needed}, and see how it pans out.

Thanks again

Alan

 

[just Tony]

Hello all,

I need some confirmation regarding my Latitude setting on my ioptron base.

After capturing encouraging first results of the moon, using my longest/heaviest telephoto gear, plonked on top of a video head and tripod, i have decided to build a wedge for it, to slightly increase the versatility of that set-up, for static lunar use {and hopefully Jupiter etc} in my little west-facing backyard {not for mobile situations}....therefore i probably only require a basic polar alignment, as i am not using motors to guide, but do need to manually tweak the image occasionally, to keep it more in position within the frame...as it moves across {to avoid major cropping when shooting for stacking purposes}.

I had thought of getting a second-hand EQ mount off Ebay for my largest set-up, but i don't want to spend too much cash for a limited use....especially as i would be over the payload limit for an EQ3-2....and a more suitable EQ5 would not be worthwhile for my limited situations {i have too much gear as it is}.

My Ioptron Skyguider Pro is ideal for my mobile/lightweight set-up, of short/medium lens gear, but not suitable for the big stuff....therefore a wedge option with my video head seems worth a shot.

I have yet to use the Ioptron yet {lack of clear enough skies to view Polaris, since owning it}, so have set my latitude on the grid at my 54.3' degrees location {marked with the red arrow}, but i am unsure if that is correct, as i would have expected the top of the grid to have 90 degrees instead of 0 degrees. Therefore i can't get my head around whether i have set it correctly, or it should be set at 35.7' degrees {from the top} on this specific grid.



I have cobbled together this wedge, which i have lined-up with the elevation of the ioptron base latitude setting, but have not fully locked it down permanently/securely yet {for a general polar alignment}...until i can confirm my latitude has been set correctly on the ioptron.

Any help or confirmation is appreciated. I'm sure it is a simple answer, but my old brain is getting older by the second.

cheers.

Your wedge has excellent triangulation which is an advantageous geometry. You’ve imitated the sine bar concept that machinists use when milling heavy steel parts at arbitrary angles, so you’re in good company. And if the tripod on the left is a “3 Series” set of carbon fiber legs, those can do nicely under mid-weight payloads. Reference the Gitzo company’s nomenclature for “series”; many other manufacturers have copied that naming convention. A 2 series would be rather undersized even with carbon construction. 4 or 5 series would be a luxury.

Too bad there’s no motor in that fluid head.

The narrowest point in a support system is its Achilles Heel. I’m guessing that the mating faces in the elevation clamp of the iOptron are not more than about 1.5 inches across, which will be flirting with strain under a mid-weight payload. You might be at about 3” for the elevation clamp in the fluid head, and all else equal, the bending stiffness of a simple beam scales as the 4th power of cross section: (3/1.5)^4 = 16X. These aren’t simple beams but the scaling math will be fairly similar.

--
Wag more; bark less.

 

[Sittatunga]

Hello all,

I need some confirmation regarding my Latitude setting on my ioptron base.

After capturing encouraging first results of the moon, using my longest/heaviest telephoto gear, plonked on top of a video head and tripod, i have decided to build a wedge for it, to slightly increase the versatility of that set-up, for static lunar use {and hopefully Jupiter etc} in my little west-facing backyard {not for mobile situations}....therefore i probably only require a basic polar alignment, as i am not using motors to guide, but do need to manually tweak the image occasionally, to keep it more in position within the frame...as it moves across {to avoid major cropping when shooting for stacking purposes}.

I had thought of getting a second-hand EQ mount off Ebay for my largest set-up, but i don't want to spend too much cash for a limited use....especially as i would be over the payload limit for an EQ3-2....and a more suitable EQ5 would not be worthwhile for my limited situations {i have too much gear as it is}.

My Ioptron Skyguider Pro is ideal for my mobile/lightweight set-up, of short/medium lens gear, but not suitable for the big stuff....therefore a wedge option with my video head seems worth a shot.

I have yet to use the Ioptron yet {lack of clear enough skies to view Polaris, since owning it}, so have set my latitude on the grid at my 54.3' degrees location {marked with the red arrow}, but i am unsure if that is correct, as i would have expected the top of the grid to have 90 degrees instead of 0 degrees. Therefore i can't get my head around whether i have set it correctly, or it should be set at 35.7' degrees {from the top} on this specific grid.



I have cobbled together this wedge, which i have lined-up with the elevation of the ioptron base latitude setting, but have not fully locked it down permanently/securely yet {for a general polar alignment}...until i can confirm my latitude has been set correctly on the ioptron.

Any help or confirmation is appreciated. I'm sure it is a simple answer, but my old brain is getting older by the second.

cheers.

Your wedge has excellent triangulation which is an advantageous geometry. You’ve imitated the sine bar concept that machinists use when milling heavy steel parts at arbitrary angles, so you’re in good company. And if the tripod on the left is a “3 Series” set of carbon fiber legs, those can do nicely under mid-weight payloads. Reference the Gitzo company’s nomenclature for “series”; many other manufacturers have copied that naming convention. A 2 series would be rather undersized even with carbon construction. 4 or 5 series would be a luxury.

Too bad there’s no motor in that fluid head.

The narrowest point in a support system is its Achilles Heel. I’m guessing that the mating faces in the elevation clamp of the iOptron are not more than about 1.5 inches across, which will be flirting with strain under a mid-weight payload. You might be at about 3” for the elevation clamp in the fluid head, and all else equal, the bending stiffness of a simple beam scales as the 4th power of cross section: (3/1.5)^4 = 16X. These aren’t simple beams but the scaling math will be fairly similar.

--
Wag more; bark less.

Third power, i.e. 8x. The second moment of area of a rectangular beam is bd³/12.

 

[Alan_W1]

Hello all,

I need some confirmation regarding my Latitude setting on my ioptron base.

After capturing encouraging first results of the moon, using my longest/heaviest telephoto gear, plonked on top of a video head and tripod, i have decided to build a wedge for it, to slightly increase the versatility of that set-up, for static lunar use {and hopefully Jupiter etc} in my little west-facing backyard {not for mobile situations}....therefore i probably only require a basic polar alignment, as i am not using motors to guide, but do need to manually tweak the image occasionally, to keep it more in position within the frame...as it moves across {to avoid major cropping when shooting for stacking purposes}.

I had thought of getting a second-hand EQ mount off Ebay for my largest set-up, but i don't want to spend too much cash for a limited use....especially as i would be over the payload limit for an EQ3-2....and a more suitable EQ5 would not be worthwhile for my limited situations {i have too much gear as it is}.

My Ioptron Skyguider Pro is ideal for my mobile/lightweight set-up, of short/medium lens gear, but not suitable for the big stuff....therefore a wedge option with my video head seems worth a shot.

I have yet to use the Ioptron yet {lack of clear enough skies to view Polaris, since owning it}, so have set my latitude on the grid at my 54.3' degrees location {marked with the red arrow}, but i am unsure if that is correct, as i would have expected the top of the grid to have 90 degrees instead of 0 degrees. Therefore i can't get my head around whether i have set it correctly, or it should be set at 35.7' degrees {from the top} on this specific grid.



I have cobbled together this wedge, which i have lined-up with the elevation of the ioptron base latitude setting, but have not fully locked it down permanently/securely yet {for a general polar alignment}...until i can confirm my latitude has been set correctly on the ioptron.

Any help or confirmation is appreciated. I'm sure it is a simple answer, but my old brain is getting older by the second.

cheers.

Your wedge has excellent triangulation which is an advantageous geometry. You’ve imitated the sine bar concept that machinists use when milling heavy steel parts at arbitrary angles, so you’re in good company. And if the tripod on the left is a “3 Series” set of carbon fiber legs, those can do nicely under mid-weight payloads. Reference the Gitzo company’s nomenclature for “series”; many other manufacturers have copied that naming convention. A 2 series would be rather undersized even with carbon construction. 4 or 5 series would be a luxury.

Too bad there’s no motor in that fluid head.

The narrowest point in a support system is its Achilles Heel. I’m guessing that the mating faces in the elevation clamp of the iOptron are not more than about 1.5 inches across, which will be flirting with strain under a mid-weight payload. You might be at about 3” for the elevation clamp in the fluid head, and all else equal, the bending stiffness of a simple beam scales as the 4th power of cross section: (3/1.5)^4 = 16X. These aren’t simple beams but the scaling math will be fairly similar.

Thanks for the comments,

The wedge was pretty much the result of trial and error, and with what i could scavenge from my junk-box of various camera gear i have accumulated over the years.

I originally tried an old Arca Swiss plate, for the long base of the wedge, but found it twisted slightly under the load, and created a noticeable wobble, so i had to swop it for the Manfrotto style {Haoge brand} one, that was originally fixed to my 400mm telephoto, and use a shorter Manfrotto style one for the platform to support the video head.

Using the two sturdier Haoge plates was far stronger, and there is no side-play where the two plates meet {although they are locked in place anyway..by the clamp}, as the bottom edges of the top plate perfectly saddle the top surface of the bottom plate.....unlike with the Arca Swiss / Haoge plate combination.

I was lucky to find the knob {which contains a small bubble level} in the junk box, which i have used to provide a 'Stop'....where the two plates meet. Although it is not required to prevent the top plate sliding forward {no need, as it is securely locked in the clamp}, but it does allow me to remove the video head/plate combo for normal use {directly on the tripod}, and replace on the wedge when needed, and in the exact position, whilst i lock the clamp down.

By chance, the position of the knob on the bottom rail also coincides with the balance point of the entire set-up {wedge, camera, 400mm lens etc}, so helps reduce the need for me to fumble around when balancing the set up.

Both tripods are Manfrotto 535 series, with the one on the left being aluminium, and the one on the right being carbon fibre, and both supposedly have a twenty kilo max load {44lb}. I don't think i have ever needed to use any of my telephotos at the steep angles that may be needed for astro stuff, so i shall have to see how that works out.

My largest/heaviest set up weighs just over 5 kilos, although if not balanced precisely, there is a noticeable lever-arm effect...especially if using the x2 Nikon tc-301 teleconverter {which adds some substantial physical length to the telephoto}.

cheers

 

[just Tony]

Hello all,

I need some confirmation regarding my Latitude setting on my ioptron base.

After capturing encouraging first results of the moon, using my longest/heaviest telephoto gear, plonked on top of a video head and tripod, i have decided to build a wedge for it, to slightly increase the versatility of that set-up, for static lunar use {and hopefully Jupiter etc} in my little west-facing backyard {not for mobile situations}....therefore i probably only require a basic polar alignment, as i am not using motors to guide, but do need to manually tweak the image occasionally, to keep it more in position within the frame...as it moves across {to avoid major cropping when shooting for stacking purposes}.

I had thought of getting a second-hand EQ mount off Ebay for my largest set-up, but i don't want to spend too much cash for a limited use....especially as i would be over the payload limit for an EQ3-2....and a more suitable EQ5 would not be worthwhile for my limited situations {i have too much gear as it is}.

My Ioptron Skyguider Pro is ideal for my mobile/lightweight set-up, of short/medium lens gear, but not suitable for the big stuff....therefore a wedge option with my video head seems worth a shot.

I have yet to use the Ioptron yet {lack of clear enough skies to view Polaris, since owning it}, so have set my latitude on the grid at my 54.3' degrees location {marked with the red arrow}, but i am unsure if that is correct, as i would have expected the top of the grid to have 90 degrees instead of 0 degrees. Therefore i can't get my head around whether i have set it correctly, or it should be set at 35.7' degrees {from the top} on this specific grid.



I have cobbled together this wedge, which i have lined-up with the elevation of the ioptron base latitude setting, but have not fully locked it down permanently/securely yet {for a general polar alignment}...until i can confirm my latitude has been set correctly on the ioptron.

Any help or confirmation is appreciated. I'm sure it is a simple answer, but my old brain is getting older by the second.

cheers.

Your wedge has excellent triangulation which is an advantageous geometry. You’ve imitated the sine bar concept that machinists use when milling heavy steel parts at arbitrary angles, so you’re in good company. And if the tripod on the left is a “3 Series” set of carbon fiber legs, those can do nicely under mid-weight payloads. Reference the Gitzo company’s nomenclature for “series”; many other manufacturers have copied that naming convention. A 2 series would be rather undersized even with carbon construction. 4 or 5 series would be a luxury.

Too bad there’s no motor in that fluid head.

The narrowest point in a support system is its Achilles Heel. I’m guessing that the mating faces in the elevation clamp of the iOptron are not more than about 1.5 inches across, which will be flirting with strain under a mid-weight payload. You might be at about 3” for the elevation clamp in the fluid head, and all else equal, the bending stiffness of a simple beam scales as the 4th power of cross section: (3/1.5)^4 = 16X. These aren’t simple beams but the scaling math will be fairly similar.

Third power, i.e. 8x. The second moment of area of a rectangular beam is bd³/12.

Thanks!

--
Wag more; bark less.

 

[just Tony]

Hello all,

I need some confirmation regarding my Latitude setting on my ioptron base.

After capturing encouraging first results of the moon, using my longest/heaviest telephoto gear, plonked on top of a video head and tripod, i have decided to build a wedge for it, to slightly increase the versatility of that set-up, for static lunar use {and hopefully Jupiter etc} in my little west-facing backyard {not for mobile situations}....therefore i probably only require a basic polar alignment, as i am not using motors to guide, but do need to manually tweak the image occasionally, to keep it more in position within the frame...as it moves across {to avoid major cropping when shooting for stacking purposes}.

I had thought of getting a second-hand EQ mount off Ebay for my largest set-up, but i don't want to spend too much cash for a limited use....especially as i would be over the payload limit for an EQ3-2....and a more suitable EQ5 would not be worthwhile for my limited situations {i have too much gear as it is}.

My Ioptron Skyguider Pro is ideal for my mobile/lightweight set-up, of short/medium lens gear, but not suitable for the big stuff....therefore a wedge option with my video head seems worth a shot.

I have yet to use the Ioptron yet {lack of clear enough skies to view Polaris, since owning it}, so have set my latitude on the grid at my 54.3' degrees location {marked with the red arrow}, but i am unsure if that is correct, as i would have expected the top of the grid to have 90 degrees instead of 0 degrees. Therefore i can't get my head around whether i have set it correctly, or it should be set at 35.7' degrees {from the top} on this specific grid.



I have cobbled together this wedge, which i have lined-up with the elevation of the ioptron base latitude setting, but have not fully locked it down permanently/securely yet {for a general polar alignment}...until i can confirm my latitude has been set correctly on the ioptron.

Any help or confirmation is appreciated. I'm sure it is a simple answer, but my old brain is getting older by the second.

cheers.

Your wedge has excellent triangulation which is an advantageous geometry. You’ve imitated the sine bar concept that machinists use when milling heavy steel parts at arbitrary angles, so you’re in good company. And if the tripod on the left is a “3 Series” set of carbon fiber legs, those can do nicely under mid-weight payloads. Reference the Gitzo company’s nomenclature for “series”; many other manufacturers have copied that naming convention. A 2 series would be rather undersized even with carbon construction. 4 or 5 series would be a luxury.

Too bad there’s no motor in that fluid head.

The narrowest point in a support system is its Achilles Heel. I’m guessing that the mating faces in the elevation clamp of the iOptron are not more than about 1.5 inches across, which will be flirting with strain under a mid-weight payload. You might be at about 3” for the elevation clamp in the fluid head, and all else equal, the bending stiffness of a simple beam scales as the 4th power of cross section: (3/1.5)^4 = 16X. These aren’t simple beams but the scaling math will be fairly similar.

Thanks for the comments,

The wedge was pretty much the result of trial and error, and with what i could scavenge from my junk-box of various camera gear i have accumulated over the years.

I originally tried an old Arca Swiss plate, for the long base of the wedge, but found it twisted slightly under the load, and created a noticeable wobble, so i had to swop it for the Manfrotto style {Haoge brand} one, that was originally fixed to my 400mm telephoto, and use a shorter Manfrotto style one for the platform to support the video head.

Using the two sturdier Haoge plates was far stronger, and there is no side-play where the two plates meet {although they are locked in place anyway..by the clamp}, as the bottom edges of the top plate perfectly saddle the top surface of the bottom plate.....unlike with the Arca Swiss / Haoge plate combination.

I was lucky to find the knob {which contains a small bubble level} in the junk box, which i have used to provide a 'Stop'....where the two plates meet. Although it is not required to prevent the top plate sliding forward {no need, as it is securely locked in the clamp},

Don’t be too quick to minimize your good idea. That completes the triangulation which features the load paths being in compression or tension (I’ll come back to tension in the next paragraph) in nature instead of torsion. Without the stop you could get torsional flexing at the clamp.

The downside of a “shoved against” stop is that if the payload center of mass will ever be on the other side of the clamp, you’re back to torsion.

but it does allow me to remove the video head/plate combo for normal use {directly on the tripod}, and replace on the wedge when needed, and in the exact position, whilst i lock the clamp down.

By chance, the position of the knob on the bottom rail also coincides with the balance point of the entire set-up {wedge, camera, 400mm lens etc}, so helps reduce the need for me to fumble around when balancing the set up.

Both tripods are Manfrotto 535 series, with the one on the left being aluminium, and the one on the right being carbon fibre, and both supposedly have a twenty kilo max load {44lb}. I don't think i have ever needed to use any of my telephotos at the steep angles that may be needed for astro stuff, so i shall have to see how that works out.

My largest/heaviest set up weighs just over 5 kilos, although if not balanced precisely, there is a noticeable lever-arm effect

A lot can be learned by grasping the farthest point of an assembly and looking at what bends under the influence of some gentle pushing and pulling. Under my tracker I used to use Kirk’s rapid swap tripod head quick releases that resemble Arca dovetails. Unfortunately the weight supporting pad extends only to about 60% of the overall width… barely beyond the centerline.

--
Wag more; bark less.