Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
06-15-2016, 07:40 PM   #16
Pentaxian
bertwert's Avatar

Join Date: Jun 2015
Location: Golden, BC
Posts: 14,819
I might try fashioning a controller after I make the rail...
But first thing first, make the rail!

I'd suggest a RPi Zero or an Arduino.
The Zeros are cheap at $5!

06-15-2016, 09:46 PM   #17
Site Supporter
Site Supporter
AggieDad's Avatar

Join Date: Jan 2015
Location: Houston, TX
Photos: Gallery
Posts: 1,103
Original Poster
QuoteOriginally posted by Transit Quote
Speaking as a cabinet maker , drawer guides have necessary play in horizontal and vertical planes
and may need to be loaded to restrict it.
Actually this set of drawer guides are not standard guides, but miniatures (about 7" long and only 5/8" wide by 3/8" thick). and are very tight (see Rockler's website). Basically they will be loaded twice - once when the platform is attached to the angles (a horizontal load), and again when the camera is mounted (vertical load).

While they could still have some play (I have not noticed any), it would be basically rendered moot as the zero-backlash nut attached to the platform is the determining factor as to the movement of the camera on its platform. Along with zero-backlash, the screw itself rides in bearings in pillow blocks.

Last edited by AggieDad; 06-15-2016 at 10:04 PM.
06-15-2016, 11:03 PM   #18
Pentaxian
Transit's Avatar

Join Date: Aug 2007
Location: Whanganui NZ
Photos: Gallery | Albums
Posts: 4,495
Cleared that up then

be fun to check what minuscule variance does exist over the travel
maybe a laser pointer and distant target ?
06-16-2016, 07:27 AM   #19
Loyal Site Supporter
Loyal Site Supporter
pacerr's Avatar

Join Date: Jan 2008
Location: Paris, TN
Photos: Gallery | Albums
Posts: 3,194
QuoteOriginally posted by Transit Quote
what minuscule variance does exist over the travel maybe a laser pointer and distant target ?
Works fine. I had a magnet epoxied to a laser pointer I was using to align parts and discovered it readily displayed microscopic vibration/motion as well if pointed at a distant surface.

Might be interesting to permanently mount a small one such as seen on power tools as a 'bore-sight' device for a camera. Flash-shoe mount? On battery grip? Could also detect camera motion/blur.

06-16-2016, 08:19 AM   #20
Veteran Member




Join Date: Jun 2015
Location: South West UK
Photos: Albums
Posts: 1,493
Quick question: what kind of control is usually available on automated versions?
I would assume number of steps and step distance, plus start/stop.
Anything else I'm missing?
Is there control over the initial start point or just start from a 'home' position?
06-16-2016, 08:35 AM   #21
Site Supporter
Site Supporter
TomTom's Avatar

Join Date: Apr 2014
Location: Dallas, Texas
Photos: Gallery | Albums
Posts: 526
QuoteOriginally posted by victormeldrew Quote
Quick question: what kind of control is usually available on automated versions?
I would assume number of steps and step distance, plus start/stop.
Anything else I'm missing?
Is there control over the initial start point or just start from a 'home' position?
Nass recently posted a review here of the WeMacro rail device, and the review has links to the manufacturer site and others that may be helpful.
06-16-2016, 09:50 AM   #22
Site Supporter
Site Supporter
AggieDad's Avatar

Join Date: Jan 2015
Location: Houston, TX
Photos: Gallery
Posts: 1,103
Original Poster
QuoteOriginally posted by Transit Quote
Cleared that up then

be fun to check what minuscule variance does exist over the travel
maybe a laser pointer and distant target ?
That would be fun. But I am on the road in the RV and won't return home until fall. So it won't be me trying it before October.

I can tell you how I focus and shoot. I start with the platform centered on the rack and use live view. I bring in the image as sharp as I can and then zoom the live view and focus even sharper, the zoom in again, etc. Eventually I am zoomed in so tight that the screen's resolution makes any fiddling meaningless. Then I switch off live view and use a wireless remote with mirror up for the shot.

While adjusting, there can be some small amount of shake on the screen, but that's to be expected - I am looking at a zoomed-in live view, at a multiplication of 2, 4, 6, 8, or 10.

Well, actually I find the screen on the K5-iis doesn't really have the resolution to be significantly useful to me past 6x. Better eyes than mine (not hard) could maybe continue to 8x. At 6x I am really looking at an area of 1/36 of the photo. The area you see on the screen will be the reciprocal of the square of the magnification, so 10x would result in you seeing 1/100 of the image you are shooting.

There are lots of moving parts involved in this process starting with the stability of the tripod. I actually have more trouble using the focusing rack when the tripod is on carpet versus concrete because there will be more image shake during the focusing process. However, once I take my hand away this dampens out almost immediately.

I am interested in the methods others use for their macro shots.

Don

---------- Post added 06-16-16 at 12:06 PM ----------

The WeMacro looks pretty neat. And when I am done all the different iterations of my design(s), I may (probably will) end up spending close to the same money.

But I am retired and have plenty of time to mess with things. In fact, I look for these types of projects. Studying the likes of the WeMacro could give me some new ideas. After all, there is no "off" switch on genius.

06-16-2016, 10:59 AM   #23
Site Supporter
Site Supporter
TomTom's Avatar

Join Date: Apr 2014
Location: Dallas, Texas
Photos: Gallery | Albums
Posts: 526
QuoteOriginally posted by AggieDad Quote
That would be fun. But I am on the road in the RV and won't return home until fall. So it won't be me trying it before October.

I can tell you how I focus and shoot. I start with the platform centered on the rack and use live view. I bring in the image as sharp as I can and then zoom the live view and focus even sharper, the zoom in again, etc. Eventually I am zoomed in so tight that the screen's resolution makes any fiddling meaningless. Then I switch off live view and use a wireless remote with mirror up for the shot.

While adjusting, there can be some small amount of shake on the screen, but that's to be expected - I am looking at a zoomed-in live view, at a multiplication of 2, 4, 6, 8, or 10.

Well, actually I find the screen on the K5-iis doesn't really have the resolution to be significantly useful to me past 6x. Better eyes than mine (not hard) could maybe continue to 8x. At 6x I am really looking at an area of 1/36 of the photo. The area you see on the screen will be the reciprocal of the square of the magnification, so 10x would result in you seeing 1/100 of the image you are shooting.

There are lots of moving parts involved in this process starting with the stability of the tripod. I actually have more trouble using the focusing rack when the tripod is on carpet versus concrete because there will be more image shake during the focusing process. However, once I take my hand away this dampens out almost immediately.

I am interested in the methods others use for their macro shots.

Don

---------- Post added 06-16-16 at 12:06 PM ----------

The WeMacro looks pretty neat. And when I am done all the different iterations of my design(s), I may (probably will) end up spending close to the same money.

But I am retired and have plenty of time to mess with things. In fact, I look for these types of projects. Studying the likes of the WeMacro could give me some new ideas. After all, there is no "off" switch on genius.
I hope that your travels go well, Don. Your method looks sound to me. Though my eyes are going down hill a little in recent years I still have good luck focusing via the OVF, so that's the only thing I might do differently, though I should practice with Live View more. I included the link to the WeMacro review to encourage ideas and talk on fine tuning your rig. Hopefully everyone will share their thoughts in that regard.

Happy trails!
06-16-2016, 03:19 PM   #24
Veteran Member




Join Date: Jun 2015
Location: South West UK
Photos: Albums
Posts: 1,493
Reading the specs in that link, I never realised that some people want micron scale steps...
With that lead screw and a 200 step/rev motor you can achieve 6.25um steps, assuming direct connection and a torquey enough motor.
But to achieve micron steps you would either need a finer pitched lead screw or some gears (8/50 would do it). The latter is preferable anyway, to avoid mechanical forces (bending/thrust) through the spindle, hurting the motor. With enough gearing you can also reduce the necessary torque and the cost of the motor and driver.
All that said, to achieve reliable accurate micron steps with zero lash would require some pretty serious engineering.
06-16-2016, 04:08 PM   #25
Site Supporter
Site Supporter
AggieDad's Avatar

Join Date: Jan 2015
Location: Houston, TX
Photos: Gallery
Posts: 1,103
Original Poster
QuoteOriginally posted by victormeldrew Quote
Reading the specs in that link, I never realised that some people want micron scale steps...
With that lead screw and a 200 step/rev motor you can achieve 6.25um steps, assuming direct connection and a torquey enough motor.
WOW! Microns! Amazing - and scary.

All I want is to get sharp enough for my old eyes and a computer screen (maybe a Mac Retina). The (potential) accuracy I ended up with is a function of the pitch of the 8 mm diameter screw which is 1.25 mm per revolution. Since it is pretty easy to turn 1/4 a revolution, that means it isn't too hard to adjust to approx. 0.3 mm.

I don't know about the micron guys, but I can be satisfied with 0.3125 mm - that's just not very much. Actually, I think I can be satisfied with 1/2 a turn. If the stepper could work to 1/8 of a turn without having to jump through hoops, then we're looking at 0.15625 mm of movement. That seems more than pretty good.

I am interested in anyone's (simple) implementation of a stepper. It would be neat to do, even though I don't need it.
06-16-2016, 04:58 PM   #26
Veteran Member




Join Date: Jun 2015
Location: South West UK
Photos: Albums
Posts: 1,493
Well, most steppers are 1.8deg/step although some are up to 7.5deg/step. So even without gearing you would be achieving much finer steps than that, assuming smooth enough bearings. Of course you can step multiple times per image.
06-16-2016, 06:59 PM   #27
Loyal Site Supporter
Loyal Site Supporter
Riggomatic's Avatar

Join Date: Nov 2014
Location: Auburn, Indiana
Photos: Albums
Posts: 3,475
I have a few steppers sitting around, an arduino and a stepper driver. Looks like a fun project.
06-16-2016, 08:37 PM   #28
Site Supporter
Site Supporter
AggieDad's Avatar

Join Date: Jan 2015
Location: Houston, TX
Photos: Gallery
Posts: 1,103
Original Poster
I hope you all keep this going until our summer road trip is over. I am ready to give it a go.
06-18-2016, 11:35 AM   #29
Site Supporter
Site Supporter
TomTom's Avatar

Join Date: Apr 2014
Location: Dallas, Texas
Photos: Gallery | Albums
Posts: 526
QuoteOriginally posted by AggieDad Quote
Actually this set of drawer guides are not standard guides, but miniatures (about 7" long and only 5/8" wide by 3/8" thick). and are very tight (see Rockler's website). Basically they will be loaded twice - once when the platform is attached to the angles (a horizontal load), and again when the camera is mounted (vertical load).

While they could still have some play (I have not noticed any), it would be basically rendered moot as the zero-backlash nut attached to the platform is the determining factor as to the movement of the camera on its platform. Along with zero-backlash, the screw itself rides in bearings in pillow blocks.
My drawer slides arrived yesterday. After inspecting them this morning I have to agree with Don. There is no play at all, and the lead screw will provide added stability. A few more parts to be purchased before I can get started.
06-29-2016, 07:45 AM   #30
Site Supporter
Site Supporter
AggieDad's Avatar

Join Date: Jan 2015
Location: Houston, TX
Photos: Gallery
Posts: 1,103
Original Poster
QuoteOriginally posted by TomTom Quote
My drawer slides arrived yesterday. After inspecting them this morning I have to agree with Don. There is no play at all, and the lead screw will provide added stability. A few more parts to be purchased before I can get started.
How goes the project?

Don
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
camera, course, drawer, focus, guides, image, lead, live, process, project, resolution, screen, screw, time, tool, tripod, view, weekend
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Project 52 PROJECT 52-8-15- Perspective- Distortion noelcmn Weekly Photo Challenges 26 04-21-2016 10:36 AM
Project 52 Project 52-8-15 - Perspective-Distortion WINNERS smf Weekly Photo Challenges 5 04-19-2016 07:24 PM
Project 52 WINNERS: Project 52-7-15 - Landscape - Cityscape scomatic Weekly Photo Challenges 5 04-27-2015 06:36 PM
End Homelessness Now! Project #15 paulyrichard Post Your Photos! 12 08-10-2009 08:45 AM
Project 52, Week 15 - Perspective DanLoc78 Weekly Photo Challenges 11 08-29-2008 09:26 AM



All times are GMT -7. The time now is 12:08 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top