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Glasseye Snapper

Member Since 11 Oct 2005
Offline Last Active Today, 07:30 PM
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In Topic: Perfect destination with good underwater conditions

Today, 07:30 PM

[t-quote name="noahnoah" post="370174" timestamp="1454774116"]

Glasseye Snapper - Thanks for the tip on the Red Sea. Just like you said I'd have to wait a few months due to water temperatures. Abu Dabab Diving Lodge is located in Egypt. I'm quite familiar with prices within Europe. For example, I can fly to Marsa Alam for only 70 USD. If I go charter, I can get plane tickets + 7 nights at a 4-star hotel in Makadi Bay for 240 USD (prices will go up later this year)  That's a lot cheaper than going to Bahamas, or the Caribbean. To be honest the only reason I have not considered this is because I did not know I could get those water conditions in Egypt. I thought I had to travel outside of Europe. I guess I have to revise this assumption? Did you take that photo in Marsa Alam? What type of camera did you use? Photo quality is excellent :) My underwater camera is probably not that good but it will suffice for now. [/t-quote]
 
The photo was taken in Sharm El Naga, a small resort between Hurghada and Safaga, but you can take similar images all along the coast. Since there are no rivers emptying in the Red Sea and no run-off of fertilizer and other pollutants water clarity tends to be excellent. Wind and waves can be an issue, especially when snorkeling because if you are tossed around by waves it is going to be hard to take good images. That is something to take into account in many places. Winds in Egypt are less during Spring and Summer and as I mentioned, in a Marsa the Northern side tends to be well-protected from the waves. Another advantage of a Marsa, especially since you are not an experience snorkeler yet, is that you can start taking pictures in water that is shallow enough to still stand and then work your way to deeper water. It is also useful to remember that in many places, including Egypt, conditions are often best early in the day before wind picks up as a result of solar heating.
 
Here are some images from a 6-7am dive along the North side of Marsa Abu Dabbab. Most are quite shallow and could be done while snorkeling. Images were taken with an Olympus OMD EM-5 in Nauticam housing. I haven't really used a GoPro to take UW images but based on what it can do with video I wouldn't be surprised if it did a decent job. Make sure you bring an image viewing device so you can check images as you take them. You will learn much quicker what works and what doesn't that way and can also be instructive for your model.
 
Bart
 
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In Topic: Perfect destination with good underwater conditions

02 February 2016 - 04:57 PM

The closest tropical reefs that also tends to have very good water clarity, easy dive/snorkel/float/wade conditions and is also VERY easy on the budget is the Red Sea. Right now water is chilly at Northern destinations (around 20C) but if you go further south or wait a few months then it gets balmy, especially close to shore.

 

You will need to do some research on places that have the type of beach and reef structure you are looking for. I prefer places with a "Marsa" where there is a sandy beach for easy entry and the Northern side tends to be very calm as the reef breaks the waves coming from the North. If you stay close to the reef edge you get interesting and colorful fish and great lighting.

 

There are many choices ranging from 5* luxury to pretty basic huts or tents. Just to give an idea of budget: a 7-night all-inclusive stay including flight from Amsterdam starts from 520 Euros to Abu Dabbab Diving Lodge (not luxury but quite nice rooms with Airco and private bathroom). It has also a long sandy beach, a very nice healthy and gently sloping reef along the North of the bay, and a more vertical and rougher wall along the South. More luxury digs at the same Abu Dabbab Marsa and elsewhere cost around 700 Euros. Prices go up later in the year but stay very reasonable.

 

Of course some are concerned about security but based on my experience I'm not concerned. There are also options to dive the Red Sea from Jordan.

 

Cheers,  Bart

 

Example of a common fish along the edge of the reef.

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In Topic: How to get really good magnification on super macro?

02 January 2016 - 08:40 PM

Hi Vigfus,

 

I find it helpful to think about optimizing macro photography in terms of resolution, magnification, and depth of field. Physics dictates that higher optical resolution automatically leads to less depth of field. So you can't have it both ways. But that only applies to the optical resolution. For instance, if you shoot 1:1 with the aperture wide open depth of field is razor thin and the optical resolution is very high. In fact it is much higher than the pixel size of the detector and much of the optical resolution is not captured while you still suffer from the loss of depth of field. What you really want is to balance the optical and sensor resolution so you don't loose more depth of field than is necessary. You could close the aperture to match optical and sensor resolution, gaining depth of field without losing resolution. Alternatively, you can increase the magnification so the smallest resolved features start to match the pixel size. In this case magnification actually helps in getting more detailed images, although depth of view will remain thin.

 

However, if the sensor resolution is already adequate then further increasing magnification will make the shooting a lot more challenging without really helping the image. In contrast it just means a loss in field of view, just like what happens when you crop in post. A typical situation is when you really close down the aperture to gain depth of view. By then you have lost so much resolution that increasing magnification isn't sensible in getting a more detailed image. There can still be reasons to do this. For instance to ensure that the subject is large enough in the view finder so you can actually make sure it is in focus.

 

The other point is working distance. The 105mm will help with that. In addition, the same wet diopter will give you more magnification on the 105mm than the 60mm. A teleconverter also gives more magnification without reducing working distance, but I would definitely prefer a 105mm over 60mm with teleconverter. If you are really into macro the 105mm will be a good investment.

 

Bart


In Topic: Olympus OM-D E-M1 low light photography questions

25 December 2015 - 06:14 PM

Hi,
just from my saltwater tank knowledge,
red light is not so much disturbing animals as white light.
But i am sure, they can see both!

Thats the same myth like red is not seen below 5m...
You will find same coralls or algae that have a bright red colour without an external light source....
Its hard to try to fix that on a picture, with or without strobe, but its existing.
Another thing is, that some marine fish have signs you can only see with infra red sources.
Specially differents between male and female.....
That makes only sense, if they can see in that specifc  range of light.

Regards,
Wolfgang

 

Red light sensitive cells in the eye and red pixels on sensors use pigments that detect a wide range of "red" wavelengths. Red at the long end of the range, and certainly infrared, does get absorbed very quickly and is virtually gone after a few meters. The reason that you can still detect red at greater depth is that light at the shorter end of the red wavelength range penetrates much deeper. Whether fish can see artificial red light depends on whether their eye pigment absorption spectrum overlaps the emittance spectrum of the dive light. The answer will likely differ for different fish and light sources.

 

Bart


In Topic: Fish ID from Raja Ampat

22 December 2015 - 05:21 PM

I agree that A. leucogrammicus is the only reasonable match. I don't have a problem with the white stripes being faint but the yellow tail and fewer spots are distinct. Would be nice to see similar patterns from other regions. If it is specific to Raja ampat it may be a regional variant or (sub)species.

 

Bart

 

PS: some Cephalopolis groupers have juveniles with yellow tails but none seem to be matching