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OzzieTraveller
21-11-2012, 10:52am
G'day all

On Sunday after days/weeks of rain & wind, we had a fine, hot & sunny day, so off I meandered to the beach to seek out some surfers & airborne “B52s” (Pelicans in real life). While sitting out on the breakwater I was approached by another camera-toting bloke who showed lots of interest in “that thing on the top of the camera”. He was asking about the Red Dot Sight that I use for birding, rodeo & camp drafting and of course, these surfers. In fact anything with fast moving activity.

I was introduced to the RDS a couple of years back when I complained to someone else that shooting moving action with the 300mm lens "aint ezy" – as soon as the subject moved sideways, I lost it from the viewfinder, and had to start tracking all over again – which meant that I lost the subject all too often. RDS sights are widely used by competition gun & pistol shooters.

As this other fella had never seen one, I thought that maybe people here don't know about them either ~ so here's a bit about them and how they work.

The RDS is a device that costs around $90 and is used very widely by film & television camera-operators for following action … following a cricket ball etc as it is airborne on its journey to the boundary is one of many uses.

Here's what it looks like :--
http://i50.tinypic.com/zvfbd.jpg

The RDS does not have a magnifying lens – rather it has an open sight and a battery-powered bright red dot reflecting off the screen. You / the operator hold the camera away from your eye and follow the fast moving action by moving the red dot with the subject and letting the camera follow- focus and shoot away while on burst. As the subject moves around, your eyes can easily follow the directional movements.

Here's a view thru the RDS: --
http://i49.tinypic.com/2vi12y8.jpg

The letterbox itself is about 75metres away from my place.


and here's the view thru the camera lens – lens is on 500mm :--
http://i50.tinypic.com/fe1d3k.jpg


and here's some of last week's images, shot using the Fuji X-s1 whose lens goes out to 625mm [ff equiv] :--


http://i48.tinypic.com/209io7t.jpg
Full frame, uncropped, lens at 625mm; 1/1500s x f5,6; iso-400; hand held,


http://i45.tinypic.com/2wrelus.jpg
Full frame, uncropped, lens at 500mm; 1/2000s x f5,6; iso-250; hand held


http://i45.tinypic.com/16k8jk1.jpg
0ne-quarter of full frame; lens at 350mm; 1/2000s x f5,6; iso-320; hand held


If the idea of having your own RDS unit appeals to you, you can probably get them from any gunshop [they are not found in camera shops] I know that Holliman's in Charters Towers has both RDS units and the camera – hot shoe adapters, so if you google for them, I'm sure that they will be able to look after you.

disclaimer - I'm not involved in the selling of these devices: this note is just an advisory for forum members
Regards, Phil

MarkChap
21-11-2012, 10:56am
Is it just me, or are the images missing Phil ??

dbax
21-11-2012, 12:30pm
I see them Mark

Rattus79
21-11-2012, 2:22pm
I see them too.

I'll tell you what, If people get photographers and terrorists confused now, just wait till you get one of these babies on your camera!!!

These'd be fantastic for motorsports! I never even thought of it before. Thanks for the share!

agb
21-11-2012, 3:04pm
How does it allow for the parallax error which occurs at the varying distances you would be focusing at?

OzzieTraveller
21-11-2012, 8:28pm
G'day mate


Is it just me, or are the images missing Phil ??

Maybe ys haven't gotcha teeth in the rite way ... :rolleyes: :rolleyes:

Phil

- - - Updated - - -

G'day Graham


How does it allow for the parallax error which occurs at the varying distances you would be focusing at?

In my case, I racked out the lens to 500mm and calibrated it there - figuring that from 500 to 625 there's not much change in direction, and for under 500mm the widening angle of view won't do any 'harm' to its accuracy

Like all good instruments, each has calibration adjusters ...

http://i45.tinypic.com/19qpfr.jpg

The 2x screws do the "X" and "Y" alignment, while the numbered dial is the brightness of the red dot
It uses a coin-battery that provided you power 'off' when not in use, goes for 30-40 hours of use

Regards, Phil

Ezookiel
21-11-2012, 8:44pm
That is possibly one of the best ideas I've seen carried across to photography in a long time.
Utterly brilliant idea.
I don't shoot action too often, but it would sure as heck help when I do.

Mark L
21-11-2012, 10:23pm
Sorry for a possibly obvious question.
This will help me follow a moving object , while letting my camera settings look after the focus etc?

arthurking83
21-11-2012, 10:52pm
Something else I'm curious about:
You say that you use this thing in the manner where you "hold the camera away from your eye".

On a non DSLR camera this won't cause any issue, but on a DSLR a potential issue could arise when Shutter Priority or Aperture Priority is used for the shooting mode.
(possibly Program Auto mode too, but I don't know as I never use that mode).

If the operators eye is not at the viewfinder whilst not in live view mode, the exposure will be affected, and the result could be inconsistent results from exposure to exposure.
Any light entering back through the viewfinder and into the optical system will affect exposure. A DSLR's metering system is embedded up in the prism housing.
Covering the viewfinder would be recommended if using this method to shoot.

Theoretically tho if live view is used on the DSLR, the metering will not be affected as the mirror is already raised and the sensor should be doing the metering.
(never tested for this myself, but I'm sure this is the case for exposure and metering tho).

Manual exposure should be used without the assistance of Auto ISO to eliminate the possibility that metering and hence exposure could be affected.

P&S and bridge cameras don't use relayed optics through to the viewfinder, so you won't see this issue.

Ezookiel
22-11-2012, 7:15am
The 60D comes with a rubber plug on the shoulder strap to put into the viewfinder to prevent light entering the viewfinder from affecting the settings. I'd guess you would use that if you were using a sight like this to shoot with.

Warus
22-11-2012, 8:29am
How's it with stability when you are waving it about in front of your body trying to track a bird moving? I guess it only works on a monpod or tripod?

agb
22-11-2012, 9:07am
Something else I'm curious about:
You say that you use this thing in the manner where you "hold the camera away from your eye".

On a non DSLR camera this won't cause any issue, but on a DSLR a potential issue could arise when Shutter Priority or Aperture Priority is used for the shooting mode.
(possibly Program Auto mode too, but I don't know as I never use that mode).

If the operators eye is not at the viewfinder whilst not in live view mode, the exposure will be affected, and the result could be inconsistent results from exposure to exposure.
Any light entering back through the viewfinder and into the optical system will affect exposure. A DSLR's metering system is embedded up in the prism housing.
Covering the viewfinder would be recommended if using this method to shoot.

Theoretically tho if live view is used on the DSLR, the metering will not be affected as the mirror is already raised and the sensor should be doing the metering.
(never tested for this myself, but I'm sure this is the case for exposure and metering tho).

Manual exposure should be used without the assistance of Auto ISO to eliminate the possibility that metering and hence exposure could be affected.

P&S and bridge cameras don't use relayed optics through to the viewfinder, so you won't see this issue.

I could see you using this with back button focus in ai servo mode, and just put your other thumb over the viewfinder to stop extraneous light coming in via the view finder. I have done a few times when my eye is not at the viewfinder, eg when the camera is on a tripod and very low to the ground.

arthurking83
22-11-2012, 3:14pm
I could see you using this with back button focus in ai servo mode, and just put your other thumb over the viewfinder to stop extraneous light coming in via the view finder. I have done a few times when my eye is not at the viewfinder, eg when the camera is on a tripod and very low to the ground.

When I take landscapes shots I use my hand just over the vf without actually touching it, or I'll drape an old microfibre cloth over it.
I think most Nikons also come with a plastic cover to protect the vf whilst in it's packaging too(I have a few of these plugs from somewhere too.

Just something to be mindful of, that's all.

OzzieTraveller
22-11-2012, 8:04pm
G'day Mark


Sorry for a possibly obvious question.
This will help me follow a moving object , while letting my camera settings look after the focus etc?

Qwik answer ... Yes
My camera is preset as AF-C; Shutter mode, somewhere between 1/1000 & 1/2500; iso = auto to 800; burst at 1,5fps to 5fps depending upon what I am trying to capture

Then I simply follow the bird / surfer / rodeo rider / whatever with the red dot on the subject and the camera clicks away like mad. At home later on, I review each sequence of images to choose the best keeper & delete all the others.

So for last Sunday's surfing I had about 90 minutes there, took about 400 frames in about 50 sequences. Many sequences have 3 to 8 sharp images, and I have kept about 20 images - I am very hard on myself .... :eek:

Regards, Phil

poorman
22-11-2012, 8:20pm
Very well thought of lazer camera

OzzieTraveller
22-11-2012, 8:22pm
G'day Arthur


Something else I'm curious about:
You say that you use this thing in the manner where you "hold the camera away from your eye".

On a non DSLR camera this won't cause any issue, but on a DSLR a potential issue could arise when Shutter Priority or Aperture Priority is used for the shooting mode .... If the operators eye is not at the viewfinder whilst not in live view mode, the exposure will be affected, .... Covering the viewfinder would be recommended if using this method to shoot. ....

Arthur - while I am well aware of the SLR camera's potential for some light 'leakage via the eyepiece' ~ in this instance I feel that your imagination is going at full steam ahead :eek: :eek:

Way back in film SLR days, my Pentax came with a viewfinder clip to lock the eyepiece for tripod-mounted imagery. Neither of my 2x current SLRs have such a device, so maybe - maybe even the makers do not consider it to be a real-huge-issue

Your other point regarding using Live View plus the RDS - nup, sorry mate. There is no dSLR in the ca-ni-px camp that I have played with in the last 24 months that has a live view system anywhere like the Sony or non-SLR superzoom cameras. The live view on my Pentax is a joke at best

Anyway - forget all about live view issues - it's a complete red herring to the RDS device

In the light of your query, I have just reviewed the hand-holding of the camera / RDS assembly ... and the distance between my eye & the RDS & camera eyepiece is "one finger length" [you will enjoy my precisional accuracy here]. I had thought that it was considerably more than this ~ so apols here for my OP mentioning of another distance

Regards, Phil

arthurking83
23-11-2012, 7:22am
... and the distance between my eye & the RDS & camera eyepiece is "one finger length" [you will enjoy my precisional accuracy here]. I had thought that it was considerably more than this ~ so apols here for my OP mentioning of another distance

Regards, Phil

That sounds roughly equal to the distance I keep my hand over the vf when doing my landscape shots .. possibly half a finger's distance, by my precision measuring device doesn't resolve down to those kinds of resolutions.

One of the nice things about the highest end Nikon's, ie. D700 and up! ... they have a viewfinder curtain. A small aperture device controlled via an easy to get too lever at the viewfinder.
Flip it closed .. flip it open.

But again this isn't the point. The point of my comment was to alert any DSLR user to this potential situation. But I'm sure that if the operator is using it as you do Phil, keeping their eye quite close to the vf without actually being at the viewfinder, then the issue may be minimal to the point of a non issue.

beaujest4
23-11-2012, 2:01pm
What happened to learning to use you camera with both eyes open. One watching the action the other through the view finder. Maybe I am too old school

OzzieTraveller
24-11-2012, 10:51am
G'day mate


What happened to learning to use you camera with both eyes open. One watching the action the other through the view finder. Maybe I am too old school

Nup - you're not too old .... :o

Using lenses up to, say 200mm the old 2-eyes trick works quite well ... it's when you get to 400, 500 & 600 that the angle of coverage is so small that if you lose sight of a moving target, it justt doesn't come back into the field of view all that easily

Using the RDS vs the 'good-ole-eyeball' is akin to modern autofocus vs manual focus ... and I know which I prefer

Hope this helps your 'confusion'
Regards, Phil